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How to calculate percentage change 2007-08-03
From Galland:
I am working on graphs and I need to find the percentage of increase from one figure to another. How do I do that? For instance staff hours for 2006 were 28011 and for 2007 were 31230. How do I find the percentage of increase?
Answered by Stephen La Rocque.
Increasing your average mark 2019-11-01
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?
Answered by Penny Nom.
Faster than as a percentage 2017-03-18
From Maximilian:
Hi, i have a strange issue with the phrase "faster than" in percentage, ie. if i have a 10MB/s connection, and somebody has a 7MB/s connection, is it 30% faster or 50% faster.- which ( affirmation, phrase, sentence ) is the right one:

a:) My 10MB/S connection is 50% faster than the 7MB/s ?
b:) My 10MB/S connection is 30% faster than the 7MB/s ?

Thanks in Advance, and please if you can teach me why !

Answered by Penny Nom.
Two increases of 20% 2016-01-27
From Z:
How do I find how many books are in a library given a problem like this... The number of books increase after buying 20% more in May. The number increased again by 20% after they were given 300 books. How many books did it start with?.
Answered by Penny Nom.
Book sales 2015-12-30
From Sandra:
Your finance text book sold 56,500 copies in its first year. The publishing company expects the sales to grow at a rate of 20.0 percent for the next three years, and by 8.0 percent in the fourth year. Calculate the total number of copies that the publisher expects to sell in year 3 and 4.
Answered by Penny Nom.
A price increase and a consumption decrease 2014-08-16
From sujan:
If the price of petrol increases by 25% and Rajesh intends to spend only 15% more on petrol then by how much % should he reduce the quantity of petrol he buys?
Answered by Penny Nom.
Percentage change 2014-05-09
From hi:
the hw club had 46 members in sept. in april, the club had 24 members. what was the percent of change in the hw club's membership from sept. to apan increase or decrease in membership? ril? what is
Answered by Penny Nom.
Percentage increase of the population of a town 2014-03-28
From hunter:
The population of a certain town in 1984 was 2900 people. The percent increase was 2.5% each year. What is the town's population in 2002?
Answered by Penny Nom.
40 meters increased by 20% 2014-03-14
From Kyle:
I need help finding out this question: 40 meters increased by 20% Is the answer 800 or is it 8?
Answered by Penny Nom.
Increasing and decreasing sales 2013-03-06
From Meghan:
Pace Design's sales increased by 30% in the first year, increased by 60% in the second year, decreased by 60% in the third year and increased by 90% in the fourth year. What was the cumulative change in sales over the 4 years?
Answered by Penny Nom.
An increase/decrease in profit 2012-03-13
From Thanikasalam:
It is understood that increase/decrease in profit for current year compared to the previous year is done by the formula (x-y)/y, with x=profit on current year and y=profit on previous year. How do we derive this formula?

If we work on this formula of calculating increase/decrease in profit, we get x/y-1

* = (x-y)/y
= x/y - y/y
= x/y - 1

How do you justify the 1 in the equation above. How to derive the formula and how do i prove it?

Answered by Penny Nom.
A 46% increase 2012-01-03
From kabilan:
increase a price of 8.24 by 46% and give the answer to the nearest penny
Answered by Robert Dawson.
A 15% increase 2011-03-22
From Abeth:
Bobby dela Cruz is the purchasing agent for school supplies of a certain university. Because of new research projects, Bobby ordered an additional 32,500 worth of supplies this month. This is a 15% increase from last month. What was the value of the school supplies that Bobby ordered last month?
Answered by Robert Dawson.
Percentage increase 2010-05-20
From Rebecca:
Question from Rebecca:

In 2008 my land was valued at $84,000. In 2009 my land was re-valued at $235,000.00. What is the percent increase between the two values? I want to be able to express "the value was increased by x%."

Answered by Harley Weston.
Percentage increase from a negative to a positive 2010-01-12
From Greg:
If a company had a net lost in 2005 of $11,234 and net income of $3231 in 2006, what is the percentage annual growth in income between the two years?
Answered by Robert Dawson.
Profit increase from 10% to 15% 2010-01-03
From taha:
A shopkeeper sold a pen for $13.20 to a make a profit 10 percent.In order to earn a profit of 15 percent,he should have sold it for?
Answered by Penny Nom.
Price increases and decreases 2009-09-02
From craig:
I work for an industry that bases it price increases and decreases on commodity pricing - Customer get confused on how/why we calculated new prices due to movement in the market - Price go up x% for every $10 of movement in the market -

For this example-
Movement went down by $30 and it is 2% for every $10 - so price decrease was 6%.
Customer's price is currently $100.
We say - $100/1.06= new price of $94.3
Customer says - $100*.94= new price of $94.

They don't understand that if board went back up $30 which would be 6% increase, they wouldn't be back at $100 if they multiplied on the price decrease.
$94*1.06=$99.64 vs. $94.3*1.06=$100 (Back to the original price)

What is the best way to explain to customer besides using this example?

Any help or info is appreciated.


Answered by Victoria West.
Percentage decrease 2009-08-04
From Bill:
How to calculate the Percentage Increase or Decrease of a $ value.
Example -
Site Spend for 01-01-2008 thru 07-31-08 was $ 3,465,660
Site Spend, 2009 YTD as of 07-31-09, was $ 1,673,405
Site Spend down what % between these two amounts ?

Answered by Penny Nom.
The retail price for an ice cream scoop 2009-07-05
From Patricia:
Hi - I am trying to figure out the fairest retail price for an ice cream scoop. We have an ice cream parlor and the cost of the ice cream we buy by the bulk container has recently been increased so now we must charge more for our scoops. We pay a wholesale price of $25.40 for 242 ounces of ice cream. The cost per ounce is $0.105. What is the formula for figuring out how much to charge retail per scoop? This is probably so simple but confusing to me. Please help. Thank you!
Answered by Harley Weston.
Percent increase from a negative number to a positive number 2009-04-21
From Brian:
I have no problem calculating year over year net profits but am having trouble when it comes to a negative.
2007 Net Profit = -110,333.00
2008 Net Profit = 66,054.00


Answered by Harley Weston.
$65.09 is 70% greater than the average price 2009-04-11
From Kelly:
Hello! I know you might be thinking that I didn't look through your previous answers, but I really did. Here's my dilemma- I have a percent increase equation that is missing the 'old" value. I know that $65.09 is 70% greater than the average price, but I do not know the average price. How do I go about finding that? I tried to set up an equation, but its throwing me off because the unknown variable is in there twice, and it's been a long time since I've taken math
Thank you for your help...greatly!

Answered by Penny Nom.
Percentage increase 2009-01-19
From Destiny:
In 1990 there were 25 springs in the park. This year there are 35 springs in the park. What is the percent increase?
Answered by Penny.
Annual percent growth 2008-12-13
From Joe:
If Wall-Mart had sales of $58,200,000,000 in the year 2002 and $90,800,000,000 in the year 2006.

1. Find what percent that increase is of the 2002 sales? I came up with (9.08*10^10 - 5.82*10^10) / 5.82*10^10 * 100 = 56.01% increase. Is this correct?

2. What was the percent GROWTH in Wal-Mart's sales from 2002-2006? I am having trouble figuring out how to do the Growth problem. I would appreciate any help.

Answered by Harley Weston.
A 10% increase in supply 2008-10-10
From Irena:
How do you find begining inventory if after 10% increase in supply you got 27.5 units
Answered by Penny Nom.
Increase pricing by 5% 2008-09-28
From Adrian:
I am working to increase pricing by 5%. If the price is 100, I would typically use the formulas 100 * 1.05 = 105, which is a $5 increase. An associate suggests I divide to get the desired increase. For example, using $100 with a 5 percent increase. I would use the forumula 100/.95 = 105.26. Thas is a 5.26 increase. Can you explain this method to me an why the different increases? Which one is correct.
Answered by Penny Nom.
A 3% increase 2008-08-18
I need to know how to do a 3 percent increase for $118,200......x's it by 3% will not work please answer fast
Answered by Penny Nom.
Percentage increase 2008-06-29
From Paul:
Could you please help me with this question. I was paying $98.00 a month for my health insurance premium, now it is up to $125.83 How much of an increase is that as a percentage increase, and how can I do this on a calculator. I'd like to know how much my increase is as a percentage.
Answered by Penny Nom.
Percentage increase in profit 2007-12-04
From Dee:
If I had a certain % increase in profits for the entire year, why can't I add the profits I made for the first 1/2 of the year to the profit I made in the second 1/2 of the year to get the total year end profit percentage? Or how can I compare the increase/decrease for each 1/2 of the year to the total % increase/decrease?
Answered by Penny Nom.
A sixfold increase 2007-10-24
From Fred:
If I have $500 and it grew to $3,000, what is the correct description of the increase? Is it a sixfold increase (sextupled), or a fivefold increase (quintupled)? When I divide $3,000 by $500, the result is six, therefore, a sixfold increase?
Answered by Stephen La Rocque.
Percentage change 2007-08-19
From nona:
If inputs increase by 30% and outputs increase by 15%, what is the percentage change in productivity?
Answered by Stephen La Rocque.
Percentage change 2007-08-13
From Karen:
I need a formula for calculating percentages in Excel. For example, we = sold 4 units of an item one month, and 105 units the next. I need a = formula to calculate the percentage increase in sales units. Also, if = 5251 were sold one month and 651 the next, what is the formula for = calculating the percentage difference? Please help, thank you.
Answered by Penny Nom.
Percentage increase and decrease 2007-06-13
From Anna:
I just want to if the following formula is used for the computation of a PERCENTAGE DECREASE:

Old Value - New Value/ Old Value x 100%

My immediate superior is under the impression that the said formula works ONLY for the computation of a percentage INCREASE. He believes that the formula for a percentage DECREASE:

Old Value - New Value/ NEW Value x 100%

On this score, I want to know the correct formula for the computation of percentage decrease. Thank you so much.

Answered by Penny Nom.
Percentage change 2007-05-01
From katie:
i no many people have asked about this but im still unsure what is percentage change i have my ks3 tomoro so please reply asap thankz
Answered by Penny Nom.
Percentage increase 2006-12-21
From Wang:
The last week of a month a car dealership sold 12 cars. A new sales promotion came out the first week of the next month and the sold 19 cars that week. What was the percent increase in sales from the last week of the previous month compared to the first week of the next month?
Answered by Penny Nom.
Percentage increase 2006-11-29
From Toya:
I have some statistics from year to year based on drug seizures.(units= lbs) e.g. in 2005 123lbs seized in 2006 1518lbs seized. now i worked out the percentage increase as to be in the thousands which from looking at the figures is correct however i don't want to say 1000% increase.

using another formula current- previous *100 I got 92%. what exactly does this 92% represent and how can i use this number when presenting my answers instead of using 1000 + %

Answered by Stephen La Rocque and Penny Nom.
Percentage increase 2006-10-15
From Amanpreet:
in yr 7, bill was 1.28 m tall, in yr 9 he was 1.67m tall. calculate his percentage increase in height
Answered by Stephen La Rocque.
Plotting percentage change 2006-10-11
From Beckie:
I have worked out a set of percentage differences which are all percentage decrease. Should i express them as a negative percentage as -20%? I also need to plot them on a graph and am not sure whether to just use the percentage difference as it is, in which case i get a positive gradient, or include a negative axis and plot them in this way, in which case i would get a negative gradient. I think the slope of the curve will be the same either way so it might not matter!
Answered by Penny.
A plant increases its height by 1/2 the first day,... 2006-03-30
From Andy:
A plant increases its height by 1/2 the first day, 1/3 the second day, 1/4 the third day and so on. How many days did it take to grow to 100 times its height?
Answered by Stephen La Rocque.
A 5900% increase 2006-03-03
From Pat:
I want to find out the % of production increase from 250 dolls a month to 15,000 dolls a month. i think it is 5900% but that seems too high.
Answered by Penny Nom.
Percent gain 2006-02-14
From Bill:
If a stock is bought at $3.50 and sold at $5.80, what percent was the gain?
Answered by Penny Nom.
Percentage increase in sound intensity 2006-01-29
From David:
I am doing some emotion response mapping. Being a composer I know how to push the heart beat tempo by a % increase of BPM in my music. I want to know how to calculate an increase in intensity of sound. Now I have 60 decibels. I want an increase of intensity by a factor n% with out going over 156 decibels.
Answered by Penny Nom.
Percentage change when you start from zero 2006-01-02
From Joseph:
I am not sure if my meaning for calculation for a percent change (C-P/P)x100) is correct. In this case, C=10, P=0, does this mean 100 percent increase from previous period?
Answered by Harley Weston.
Percent change 2005-12-17
From Marie:
What is the percentage change when 1500 becomes 2000?
Answered by Penny Nom.
Percentage increase 2005-12-15
From Luiz:
I would like to know how much net income in % we have increased from 2005 to a 2006(projection).
2005 Net Income Actual: $1,599,887
2006 Net Income Budgeted: $2,067,339

Answered by Penny Nom.
Percentage increase 2005-09-19
From Dory:
Last year sales was 120,000 $ and this year sales is 280,000 $, there was an increase in sales. what I would like to know is the percentage increase between the years with the formula.
Answered by Penny Nom.
Is this percentage change or percentage increase? 2005-08-15
From Betty:
When calculating a percentage, if the formula is A(new) - B(old)/A(new) Is this percentage change or percentage increase?
Answered by Penny Nom.
Percent change 2005-07-01
From Betty:
Can you tell me the difference between Percentage Change, Percentage Increase, Percentage Difference and please give an example of each, I am very visual.
Answered by Penny Nom.
A 5% increase 2005-04-27
From Debra:
How can I determine the increased percentage of a dollar amount? I.e.: One dollar amount is $202 and another is $150, how can I determine the 5% increase from last year on the $202 dollar amount?
Answered by Claude Tardif.
Percentage increase 2005-04-19
From Tom:
What is the percentage increase from (negative -$9262.00) to (positive $3840.00)?
Answered by Penny Nom.
Cost before the markup 2004-11-23
From Norman:
the sum of eg $130 includes the markup of 30%. However I need to calculate the percentage to apply to the $130 to assess the cost ie $100.
Answered by Penny Nom.
A 40% reduction 2004-11-10
From Cathy:
I'm having trouble figuring out how to figure a percentage??? it's easy to find what 40% of any given number is, but how would i accurately figure out what is the final number is when i know the number after the 40% has been removed? when i add 40% to this number it obviously is lower than it should be. the best i could figure is; x=?-40% ---------------> x-?=-40% i'm all confused????
Answered by Penny Nom.
A 40% increase in garage space 2004-10-20
From Dianna:
A bus company recently expanded and no longer has enough room in its garage for all of its buses. Twelve of the buses have to be stored outside. If the company decides to increase their garage space by 40%, this will give them enough room for all of their current buses, plus enough room to store another twelve in the future. How many buses does the company own?
Answered by Penny Nom.
Percent increase 2003-12-24
From Frank:
How does one figure the percent of increase or decrease in the cost of an item?
Answered by Penny Nom.
Knitting gauge and felting 2003-10-27
From Sara:

I wish to create a pattern to knit an item that will then be felted, thus, shrink as a result. In order to determine the proper gauge to use in creating the item, I produced a gauge swatch, noted the original properties and then the post-felting properties. They are as follow:

Before Felting:

20 stitches(width) x 20 rows(height)yielded:
Gauge: 3.2 stitches(width) and 4 rows(height) = 1"
Dimensions: 6.25"(width) x 5.25"(height)

After Felting:

20 stitches(width) x 20 rows(height)
Dimensions: 4"(width) x 3"(height)

How do I calculate the percentage change in size to accurately determine the number of stitches and rows needed to produce the desired dimensions for the finished (felted) item?

Answered by Penny Nom.
Maine and Nevada 2003-10-24
From Jimmy:

From 1989 to 1990, the population of Nevada increased b y 157,000, and that of Maine increased by 30,000. In 1990, the population of Nevada was 1,206,152, and that of Maine was 1,233,223. If the populations of the two states continue to increase at the same rates, when will the populations of Nevada and Maine be the same?

Write a verbal model for this problem
Write an equation for the model
Solve the equation and answer the question.

Answered by Penny Nom.
Percentage decrease in sales 2003-07-31
From Linda:
If I had sales in January of 2002 that were $42,493.73 and sales that were $37,281.59. The difference is $5374.50. What is the percentage of decrease in sales?
Answered by Penny Nom.
A 40% markup 2003-06-12
From Nick:
I am attempting to determine the Retail price of an item that costs me 11.00. Our company wants to sell it at a markup of 40%. I calculated this two ways, first the way I thought it should be done. Second, the way the calculator does it (and my accountant).

  1. Cost + Cost*(percentmarkup/100)= retail price 11.00 + 11.00*.40 = retail price 11.00 + 4.40 = 15.40 retail price

  2. Using the calculators Mark Up key the answer is 18.33. Or 7.33 more than the cost or 67%.

I am confused by this Mark Up key and how it calculates. I used a cost of $10.00 and marked it up 50%. I thought it should equal $15.00 but the calculator says $20.00? This seems to be 100% markup, yes?

Can you explain the difference between the way I did it and the way a Business calculator does it?

Answered by Penny Nom.
25% more 2003-01-16
From Charlie:
If I buy something for $10 and want to sell for 25% more, do I multiply by 1.25 or divide by .75? Or another way - why do I get $13.33 when dividing by .75 ?
Answered by Penny Nom.
How do start from 2700 and get 35% back out? 2002-09-09
From Dennis:
2000 x 0.35 = 700 + 2000 = 2700
How do start from 2700 and get 35% back out? If I have 2700, how do I figure out that 35% of 2000 is 700 and adding the two them together will get me 2700?

Answered by Penny Nom.
Percentage 2002-07-20
From Sally:
If 20% of 100 is 80, then why is the percentage difference between 80 and 100 25%.
Answered by Penny Nom.
Percentage difference 2002-03-08
From Tedd:
Can you give me the formulas for calculating percentage differences between two numbers? For example: if the first number is 10 and the second number is 15, then the second number is 50% larger than the first number. However, the formula to calculate that percentage won't work if the first number is greater than the second number as in the following example: The first number is 15 and the second number is 10, with the second number being 33.3% less than the first number. Or maybe I'm mistaken and the same formula will work in both situations.
Answered by Penny Nom.
A 7% increase 2001-12-12
From Lorraine:
how do you calculate an old salary if the only information you have is current salary and the percentage increase received. For example if I make $15.86 an hour and I received a 7% increase, how much did I used to make?
Answered by Penny Nom.
Percentage increase 2001-02-17
From Bob:
If sales for jan 2001 are 154 vs 105 for 2000 - the increase total presented to my office is +46% - how does that compute. Please give me the equation.
Answered by Penny Nom.
Increasing the weight 2000-03-23
From Lee Millard:
A weight of dimension a, b is to have its weight increased by w% by bolting plates of the same material along the top and one side (but not at both ends). The top plate and side plate have the thickness, x. Find the thickness of the plates for a given weight increase of w%.
Answered by Penny Nom.
Percent of improvement 2000-01-30
From Steve Quigg:

In a 1998 survey, 21% polled responded favorably to a question. In 1999, 31% responded favorably.

What is the percent of improvement?

Answered by Harley Weston.
Percentage increase 1999-10-03
From Ann Allen:
I am a a student in the 12th grade. I need to know how to calclulate the following: A percentage increase from 2.0% to 9.5% is what percentage?
Answered by Harley Weston.
Percentages 1999-03-16
From Beth Barton:
If I have two figures and want to know the difference between them, in Percentage, how do I proceed with a calculation?

Example: 67,800 - 56,000 = 11,800
What percentage does this difference represent?
Answered by Jack LeSage.




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