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 Topic: average
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From Elena:
After 9 weeks Mikayla has an average ark of 5 out of 10 in the weekly spelling tests. What is the minimum number of extra weeks now required to raise her average to 7?
Average savings 2019-09-06
From Puchu:
A student was saving an average of £2 per week for 25 weeks. He then found a part time job and after total of 45 weeks his average savings rose to £9 per week How much did he save over 20 weeks after finding job?
The average height of a wall 2019-08-15
From Jeff:
Trying to figure the average height of a sloped foundation wall.
The lowest point is 24 inches or 2 feet.
The highest point is 116 inches or 9’ 8 inches.
Can this be figured without the degree of slope or can we assume it is Equaled sloped from point a to point b. Thanks

Why Mean? 2019-05-08
From Jill:
A group of teachers were trying to figure out why the”mean” is called mean - do you know??
How many students passed the test? 2018-07-20
From florian:
In Mr. Edgecomb's math class, 30 students took an exam on statistics. If the average passing grade was 84, the average failing grade was 60, and the overall average was 80, how many students passed the test?
How many pet dogs? 2017-09-26
From Michelle:
In 2016 there were about 135 million households in the United States. 36.5% of the households own at least one dog. On average, these households have 1.6 dogs. How many millins of pet dogs were in the United States in 2016?
Average price 2017-09-15
From Annette:
If I sold a widget at \$15.50 17.5% of the time and \$16.50 88.5% of the time what is the algebraic expression for that. How do I arrive at an average price
The average rate of change of cot(t) 2017-01-18
From Brianna:
Hello! It's been a while since I've taken a math course, and I'm stuck on a problem in my calculus course.
The question is this:

Find the average rate of change of the function over the given interval.
h(t)=cot(t) a) [5pi/4, 7pi/4]

How can he raise his average to 90? 2015-12-29
From Raj:
Harris has an 87 in a class where daily works count 20%, quizzes count 20% and tests count 60%.
If there are only two test scores what must the score on his second test to raise his average to 90?

Average rate for a return trip 2015-03-14
From Michael:
Jeffrey drove to a town 25 miles away at an average speed of 50 miles per hour. The return trip along the same route took 20 minutes longer than the trip to town. Determine the average speed in miles per hour for Jeffrey's round trip.
A train from Vancouver to Whistler 2015-02-02
From Tea:
Serena and Nina are taking a train from Vancouver to Whistler, a 160km trip. If the average speed is decreased by 16km/hr, the trip will be 1/2 hours longer. What is the average speed of the train? Thanks :)
The average of 9 numbers is 45 2014-09-12
From rizza:
The average of 9 numbers is 45. If 90 and 88 are added to the set of numbers. What will be the resulting average?
The average age of a group of 10 students 2014-09-11
From sujan:
The average age of a group of 10 students was 20. The average age increased by 2 years when two new students joined the group . What is the average age of the two new students who joined the group?
Answered by Robert Dawson and Penny Nom.
What is the average of first 100 even numbers? 2014-08-02
From Faizan:
What is the average of first 100 even numbers?
A word problem concerning averages 2014-07-26
From Bernie:
The average weight of a team of children is 50kg, Todd who weighs 56 kg then joins the team. The average weight of the new team is 51. How many children in the original team?
From Roy:
May I ask if it is correct to add the following with units included? Some tell me that the units cannot be included in the addition because we cannot add speed.
What was the class average? 2012-04-20
From olwale:
a class which consist of 15 boys and 10 girls sit for a test. the average score of the boys is 20 and the girls' is 25. find the average score of the class.
Mean and Average 2012-01-03
From john:
what is the difference between average and mean
The average age of 300 cars 2011-11-22
From Jason:
I have 300 used cars built from 1970 to 1980, I would like to know the average age by total volume. If I provide the qty built per year, can I determine the average age of the lot (300) by total volume?
 Total built Year built 50 56 30 10 30 25 64 9 12 14 1971 1972 1973 1974 1975 1976 1977 1978 1979 1980

Thanks

The average speed for the whole journey 2011-10-30
a train travels 68 Km at an average speed of 51Km/h. It then travels another 20Km at an average speed of 40Km/h before reaching its destination. Calculate the average speed for the whole journey?
Find his income on the fourth week of August. 2011-03-22
From Abeth:
The average weekly income of MJ for the first three weeks of August was 3,600 and his average weekly income for four weeks is 3950. Find his income on the fourth week of August.
Average speed 2011-03-07
From West:
Calculate the distance (in km) that Larry runs if he maintains an average speed of 8km/hr for 45 minutes
The average over two semesters 2010-01-20
From edy:
6 courses have an average of 100 in the first semester 5courses have an average of 90 in the second semester what is the average of the two semester , method of calculation , how come to have 95.4545
Average speed 2009-09-11
From john:
Sally travels by car from one city to another. She drives for 20.0 min at 68.0 km/h, 40.0 min at 37.0 km/h, and 51.0 min at 77.0 km/h, and she spends 12.0 min eating lunch and buying gas.

What is the average speed for the trip?

Average speed 2009-08-20
From Christina:
We ran 3.4 miles in 40 minutes. What was our average speed?
Averaging percentages 2009-06-14
From Alan:
Can you add percentages and then divide them by the number of percentages to get the average percentage. I.E day 1 100% day 2 100% day 3 95% average= 98.3%

is the above possible or is it not done, I have a dispute with a work colleague over this.

many thanks

Driving to school and back 2009-05-17
From marylyne:
suppose you are late for school and you drive from your house at a constant rate of 70 mph.when class is over, you drive home at a more leisurely 50mph. what is your average speed?
Mean 2009-05-02
From debra:
a hot dog sales per week monday, 100 = tuesday,87 = wednesday, 95 = thursday, 125 = friday, 210 = saturday, 250 = sunday, 57 = what is the mean sales per day?
Interest rate over two periods 2009-04-12
From Kenneth:
Hello:

How is the average determined for the following amount if it earns compound interest?

Here are my calculations, but I'm not certain that they are correct: Initial amount invested \$500.00:

\$500.00 @ 5% = \$525.00.

\$525.00 @ -2% = \$514.50.

\$14.50/\$500.00 = 2.9% divided by 2 equals an average of 1.45%.

If this average, 1.45%, is correct, how can I use 5% and -2% to determine the same average? Is it possible?

A trip at two different speeds 2009-03-28
From A student:
Good afternoon!

An automobile travels 4 hours at an average speed of 42MPH. How much longer must the truck travel at an average speed of 55MPH so the average speed for the total trip will be 50MPH?

Whitney's average test score was 79 2009-01-30
From dawn:
After 5 tests, Whitney's average test score was 79. After she scored 85 on the 6th test. What was her new average?
Average and total 2009-01-10
From cecil:
the average of six number is 84. what is the total
Answered by Stephen La Rocque and Penny Nom.
A weighted average 2008-11-27
From Kenneth:
I am interested in determining the answers to the following question by using some type of weighted average:

An investor has \$30,000 to invest at simple interest in two accounts. One account earns 2% and the second earns 5%. How much must he invest in each account if his total return is 4% or \$1,200?

The average height of an attic 2008-09-12
From oliver:
I need to find out the average height of a specific volume/area.
a standard house shape side walls height 10m, height in centre of house 15m.
width 15m length 25m (the roof spans the width)
Within the house in the corner there is a (box shape) room which is 5m in height by 3m wide and 4 m long
How do i work out the average height of the space directly above the room (same floor area)?

Answered by Stephen La Rocque and Harley Weston.
What will be the resulting average? 2008-09-05
From jean:
the average of 9 is 54.if 84 and 90 are added to the set of numbers ,what will be the resulting average?
The average rate of change 2008-03-29
From Tom:
For the function x/3x-1 find the average rate of change between the interval x=1 and x=5?
Average and mean 2008-03-17
From A student:
Mean and average are the same propeties of the set of elements, if there is average then why mathematician need the mean ?
Average speed up and down a hill 2008-03-09
From Judith:
An old broken-down ar has to travel a two miles route, up and down a hill. Because it is so old, the car travels the first mile - the ascent - at an average speed of fifteen miles per hour. How fast must it cover the second mile - the decent - to achieve an average speed of thirty miles per hours? (There is a missing variable, but what is it?)
Stacks of blocks 2008-02-07
From Tammy:
i need help for my son he is given 3 stacks of cubes. the 1rst stack has 3 the 2nd stack has 2 the 3rd stack has 4 the question is draw the stacks of cubes so they are arranged correctly to find the mean. what is the mean of the data?
Answered by Stephen La Rocque and Penny Nom.
How old is the 11th person? 2007-12-08
From Jamie:
Ten people are in a room, and their mean age is 15. After another person enters the room, the mean age is now 18. How old is the person that walked in?
Answered by Jesse McLeod and Stephen La Rocque.
Six crates of cantaloupes 2007-11-05
From BARBARA:
The average weight 6 crates of cantaloupes is 61 lbs, if 3 of the crates weigh 72, 59, and 70 lbs. which of the following could be the weight in pounds of the other 3 crates?
a. 49,59,60
b. 51,53,54
c. 53,57,58
d. 54,56,60
e. 57,57,57

Answered by Stephen La Rocque and Penny Nom.
The aggregate percentage for the year 2007-10-11
From Lisa:
I would like to add up twelve percentages then divide it by 12 to get the aggregate percentage for the year. How do I accomplish this task? Thanks.
The average rate of change of a function 2007-10-11
From vern:
Find the average rate of change of the function over the given interval. Compare this average rate of change with the instantaneous rates of change at the endpoints of the interval. f(X)=sinX for the inverval [0,pi/6]?
calculating percentages for my class 2007-10-09
From Cori:
I teach a class in which there are seven projects/quizzes worth 10% each, and the midterm and the final are each worth 15%. No problem figuring out their final grade, but I have to give a mid-term average, having only FOUR of the seven 10% things, and the midterm test. The closest I've come to an accurate "average" is to just add them together (as equals) and average them.
Answered by Victoria West & Harley Weston.
The change in an average 2007-08-19
From farah:
the average height of a group of 25 students goes up by 2 cm when astudent of height 165 cm replaces a student from the group.what is the height of the boy who went out of the group?
What was the average? 2007-08-08
From Leroy:
A total of 50 juniors and seniors were given a math test. The 35 juniors attained an average score of 80 while the 15 seniors attained an average of 70. What was the average score for all 50 students who took the test?
Average annual earnings per share 2007-08-07
From Arul:
A corporation with 5,000,000 shares of publicly listed stock reported total earnings of \$7.20 per share for the first 9 months of operation. During the final quarter the number of publicly listed shares was increased to 10,000,000 shares, and fourth quarter earnings were reported as \$1.25 per share. What are the average annual earnings per share based on the number of shares at the end of the year?
Average speeds 2007-06-22
From Dee:
A guy goes 3.1m a second for 29 seconds in a golf cart. He then walks 1.5 meters a second. How long does he have to walk to get the average speed of 2.1m a second?
The "mode" of a set of numbers 2007-06-06
From Anthony's mom:
we have a graph: Kindergarten has 1, 1st has 5, 2nd has 4, 3rd has 3
is the mode "1st grade" because there are more children in that grade?

How to increase your average 2007-05-24
From Janna:
after taking 4 quizes your average is 71 out of 100. what must your average on the next 5 quizes be to increase your average to an 81 out of 100?
Average 2007-05-06
From michelle:
the average of x and y is 20. If z = 5, what is the average of x, y, and z.
From vince:
If your homework grades is only 15% of the total grades and with an average homework grade of 90% what is your earn point for the homework earn point = average times percent
Producing chocolate bars 2007-04-26
From anne:
If you have to produce an average of 114 bars of chocolate over 7.5 hours how many do you have to produce over 9.5 hours.
Approximate average speeds 2007-03-19
From Anne:
A bicyclist pedaled up a 2 mile long hill averaging 4 miles per hour. Upon reaching the top, the bicyclist headed down a 6 mile descent averaging 26 mph. What was the bicyclist's approximate average speed? Thanks very much in advance!!
Answered by Stephen La Rocque and Penny Nom.
The average of 3 tests 2006-12-12
From Charles:
If you average 84 on first three test and the first score was 67. The second score was 7 less than the third score. What was the score on the second and third test.
From Patricia:
Your quiz grades are 73, 75, 89 and 91. What is the lowest grade you can obtain on the last quiz and still achieve an average at least 85?
Answered by Stephen La Rocque and Penny Nom.
Power walking 2006-07-30
From Wendy:
I have an exercise routine of 'power walking', approx. 5-6 days per week. I carry a pedometer with me during these walks so that I can keep track of the distance of each walk. I've created a weekly walking chart on my computer, so each time I get back from a walk, I enter my stats, such as kilometers and miles walked that day, as well as my start and finish time. At the end of each week, before I printed out my completed chart, I would calculate out what my average walking distance was, for that particular week.

At the end of each month, I would calculate:
[1] I'd add up my total kilometers and miles walked for that month. (a no brainer ~ I could do that one!)
**But also, I would work out the percentages of the following:
[A] What my average daily distance p/walk was, for that month
[B] What my average time spent, per walk was, for that month

The average of a function 2006-04-11
From Justin:
Find the average value of the following function from x=0 to x=7 f(x)=3x+4
The average of monthly averages 2006-04-06
From Ray:
I have the averages of some data in percentages. the data is rather large, how can i find the average of these averages without going back to the original data? Is there a Factor or Constant that i could multiply or devide or add and get the average of these averages without resorting to the raw data.
Answered by Steve La Rocque and Harley Weston.
Divide the product of three consecutive positive integers by their mean 2006-03-12
From Sandy:
When I divided the product of three consecutive positive integers by their mean, I got 99. What is the smallest of the three numbers?
The average of 4 numbers is 5. 2006-01-02
From Sheri:
The average of 4 numbers is 5. I have 3 of the numbers already- 5,8,4,? How do i find out what the last number to give me the average of 5?
Mean and average 2005-12-22
From Jerry:
This is just a question from a degreed engineer that has a "understanding" problem. please go to http://www.metrika.com/3medical/hemoglobin-m.html

At the end of the page they talk about "mean" vrs "average" there does appear to be a difference. What is it?

Mathilda and Matthew 2005-12-18
From A student:

Question: 1) The average of 12 is 5. The average of of 8 of these numbers ia 6. What is the average of the other four.

2)Mathilda is playing a mathematical game with Matthew. Each player starts from a point, then moves in a straight line to a second point,then to a third and so on. The moves are not made randomly, but are determined by a mathematical rule. The object of the game is to find the rule. It is Mathilda's turn to move on the grid . She starts at point M (3,9), moves to point N (2,4) and then to point O (0,0). Given Mathilda's rule, what could be the coordinates of the next point to which she might move?

Half way between 2004-09-08
From Ben:
Find the number halfway between the number shown

751,843

X bar 2003-11-04
From mary:
Remind me what this means:

```    _
X
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Means 2003-10-28
From Abdu:

Question:
80,80,84,85,88,92,97,98

The average of the 8 numbers listed above is 88. Of the following which pair of numbers could be removed from the list without changing the average.

A. 80 and 97
B. 80 and 98
C. 84 and 92
D. 84 and 97
E. 85 and 92

Answered by Andrei Volodin and Penny Nom.
Averages of Averages 2002-12-21
From Amy:
If in the month of October the % of Payments Received was 80.74% and in November it decreased to 69.36%. Can you take the 80.74-69.36/69.36 to get the % of difference. In otherwords can you take the % of difference when the numbers you are comparing are %'s????

Can you also take an average of an average? For example, average number of payments received in October was 25.00%, average number of payments received November was 50.00%, and the average number of payments received in December was 15.00%. Do you average (25.00%, 50.00% and 15.00%) or do you have to go back to the numbers that calculated the averages. For example, October 25.00% was based on 25 payments being received out of a possible 100. So instead of taking the average of the averages, do you take the average payments and the average customers over the 3 months and calculate the average???

From Richard:
I'm using a grading program for the first time this year. (ok, that's not a question) I require my students to record their grades in a Scorekeeper when they get them back. I'd like to know if my students can keep up with averaging their grades just as the grading programs automatically averages them when I put them in the spreadsheet.
Answered by Penny Nom and Claude Tardif.
The mean distance travelled 2002-06-07
From A student:
If Rosalia travels 1000 km
Sheree travels 280 km
Daniel travels 50 km
Mica travels 200 km
Connor travels 500 km
Eric travels 250 km
Hillary travels 300 km

What was the mean distance travelled?

How do you arrive at the answer?

The average of two averages 2002-05-22
From RJ:
in a class with 22 students, the average garde on an exam was 68%, in another class with 32 students, the average grade on the same exam was 78%, what was the overall for the two classes? round your answers to the nearest whole number.
Number conversions and averages 2002-02-03
From A student:
A table has the measurements of 1.6m by 2m, how much material is needed to cover table? I converted to cm then multiplied but got an answer of 32000cm ,so I divide by 100 to get to metres - the answer was 320 which I know is wrong - please explain!!

Also I need to explain in my own words what an 'average' is and I am struggling.

The average of two polygons 2001-10-23
From Irene:
How can I prove that the average of two polygons will give me another one?
What did the girls score on average? 2001-07-20
From Rajesh:
The students of two schools were sitting the same test. The students attending the first school scored 74 on average; within this the average scores of the boys and the girls were 71 and 76, respectively. The corresponding scores in the other school were 84, 81 and 90, respectively. If the average score of all boys was 79, what did the girls score on average?
The average value of a continuous function 2001-05-08
From Esther:
The average value of a continuous function y = f(x) on the interval [a,b] is given by ________________?
Average speed 2001-05-01
From Tom:
A ship goes in one direction, west to Hawaii, at 20 nautical miles per hour and, because of the wind, makes the return trip at 30 nautical miles per hour. What is the average speed?
Lots of coins 2001-04-26
From A student:
I purchase 2 million coins at 9.75
I purchase 1 milion coins at 8
what is the formula to calculate my average cost?

A few problems 2001-04-22
From Carol:
Hello I am a College student trying get through my elmentry concepts class. I am also working with the middle and elementry school student with their work. I was given a few problems to work on and i am having a hard time explaining them to students. DO you think you can help with a coupld of these questions!
Cincinnati to Winston-Salem 2001-01-23
From Belinda:
Joan Bedney travels from Cincinnati to Winston-Salem at an average rate of 40 miles per hour and returns at an average rate of 60 miles per hour. What is her average speed for the trip?
Answered by Leeanne Boehm and Claude Tardif.
What is the difference between Mean and Average? 2000-12-13
From Julie:
What is the difference between Mean and Average? My thinking is the average, is the equal to the sum of all numbers divided by the number of numbers added together. But the mean, I think should be calculated by adding the largest and smallest numbers in the set and them dividing by 2. (which is the point where 1/2 the numbers are higher and 1/2 the numbers are lower)
Answered by Patrick Maidorn and Penny Nom.
Expected number 2000-11-02
From James:
1)There are 40,25,50 students in the traditional,reformed,and reformed traditional Calculas sections taught by three teachers. On one fine day the three sections congregate together to watch the NOVA video tape on Fermat's Last Theorem.

a) A student is randomly selected from he crowed of students.What is the expected number of students in the same section of this student?

****this question which i did not have any idea to do as follow for the part b
b) If one of the three teachers is selected at random, what is the expected number of students taught by is teacher?

Mr. Edgecomb's math exam 2000-09-17
From Rachel:
In Mr. Edgecomb's math class, 30 students took an exam on statistics. If the average passing grade was 84, the average failing grade was 60, and the overall average was 80, how many students passed the test?
Sample variance 2000-04-16
From Jonathan Freeman:
I was just reading your article entitled "A Note on Standard Deviation" I'm now teaching a unit on s.d. and my students were wondering why one uses a denominator of n for a population and n-1 for a sample. I saw in your article that this is because "[the quantity] tends to underestimate sigma... and other technical reasons." To which my students again asked... "Why?" Could you please elaborate a bit on the "other technical reasons" perhaps in terms a high school senior (or their teacher...) could understand?
Word problems 2000-03-31
From Amy:
Question:
1. a north bound train left at noon. four hours later a south bound train left the same station. at 5 o'clook they were 160 miles apart. what was the rate of both if the north bound train was going 20 miles faster than the other one.
2. clark's final exam was given 5 times the weight of the weight of a weekly test. the avgerage of 15 weekly test was 91. the overall weighted average was 85. what did he make on the final.

Travelling from A to B 2000-03-20
From Matt:
A car is traveling from point A to point B. Point A and point B are 30 miles apart. A car travels 30 miles an hour from point A to point B and then goes back to point A. How fast does the car have to go back to average 60 miles an hour?
.400 in Baseball 1999-12-15
From Nieve Nielson:
I have several questions to ask about the probability of getting a .400 in baseball:
1. What is the probability of a baseball player hitting a .400 in one game, considering that the hitter is up to bat four times?

2. What is the probability of a baseball player hitting a .400 in a season, considering that there are 100 games in a season? With the first two questions in mind:

3. Considering that baseball has been around for about 100 years, about how many people should hit .400 inthat time?

The sixth game 1999-11-16
From Stephanie Sprunger:
Janice scored 18,21,27,16,and 19 points in five basketball games. How many points must she score in the next game to raise her average to 22 points per game?
The average rate of change of a function 1999-04-20
From Tammy:
Suppose that the average rate of change of a function f over the interval from x=3 to x=3+h is given by 5e^h-4cos(2h). what is f'(3)? I would appreciate any help with this question.
The halfway mark 1999-04-20
From Sherry & Tom McGee:
How do you figure the halfway mark between 1/3 and 2/3 as a fraction and a decimal point?
Prime dates 1999-03-25
From Jessica Brown:
I'm asking how do you figure out all the prime numbers in a year and, whats the average amount of prime numbers per week.
Answered by Jack LeSage and Penny Nom.
Mean and Standard Deviation 1998-04-22
From Kit:
i have a problem of maths.
i think the level of the question is secondary. question: Find the mean and the standard deviation of the numbers:1, 3, 4, 5, 7. i hope u solve this question.
thank you so much!