 |
|
|
|
|
|
|
|
|
The rate of change of the concentration of a solution |
2007-10-30 |
|
From Nicholas:
A barrel initially has two kg of salt dissolved in twenty liters of water. If water flows in the rate of 0.4 liters per minute and the well-mixed salt water solution flow out at the same rate, how much salt is present after 8 minutes?
I tried working backwards given the answer but I can't seen to get their answer of ~1.7kg. Any help would be great! Thanks
Answered by Harley Weston. |
|
|
|
|
|
|
Dividing a segment into 3 congruent parts |
2007-10-30 |
|
From Carolyn:
I am doing construction. I have a line segment drawn. I need to divide a segment into 3 congruent part. How do I do that?
Answered by Penny Nom. |
|
|
|
|
|
|
Compatible numbers |
2007-10-30 |
|
From Gary:
How do I estimate the quotient. and then tell what compatible numbers were used. 703/7
Answered by Penny Nom. |
|
|
|
|
|
|
An irrational number |
2007-10-29 |
|
From Clara:
Find an irrational number between 0.53 (with 53 as repeating)
and 0.54 (with 54 repeating)
I changed each to 53/99 and 54/99 with 1/99 being the difference.
Please help me.
Answered by Stephen La Rocque, Penny Nom and Harley Weston. |
|
|
|
|
|
|
The sum of the ones |
2007-10-29 |
|
From Hangsun:
When 2 two digit numbers are added what is the greatest possible sum of the ones?
Answered by Penny Nom. |
|
|
|
|
|
|
Constantly accelerated motion |
2007-10-29 |
|
From Priyanka:
A, B and C are three points lying in that order on a straight line. A body is
projected from B towards A with speed 3 m/s. The body experiences an
acceleration of 1 m/s^2 towards C. If BC =20 m, find the time taken to reach C and
the distance travelled by the body from the moment of projection until it reaches C.
Answered by Stephen La Rocque. |
|
|
|
|
|
|
Variation |
2007-10-29 |
|
From deeqa:
1. A car traveled 175mi at a certain speed. If the speed had been 20mph faster,
the trip could have been made in 1hr less time. Find the speed
2. The average weekly allowance A of children varies directly as their grade level, G.
If the average allowance of an 8th-grade student is $8.56 per week, what is the average
weekly allowance of a 5th-grade
The time T required to do a job varies inversely as the number of people P working. It takes 2hr for 4
working. It takes 2 hrs for 4 volunteers to distribute flyers to a neighborhood. How long would it take 12
volunteers to complete the job?
Answered by Penny Nom. |
|
|
|
|
|
|
The height of an isoceles triangle |
2007-10-29 |
|
From Maura:
I am trying to calculate the height of an isoceles triangle but in this case AB is not equal to AC.
How do I calculate this?
Thank you,
Maura age 13
Answered by Stephen La Rocque. |
|
|
|
|
|
|
The length of the side of a triangle |
2007-10-28 |
|
From devon:
hay ok i have the height of a triangle but how do i find the length od the side if all of the sides are the same length
Answered by Penny Nom. |
|
|
|
|
|
|
Area of a garden |
2007-10-28 |
|
From Megan:
My dad and I are working on a math problem and we have to find an equation to represent the area of the garden.
The garden is a 45 by 45 garden. One side of the garden butts up against the house.
Answered by Penny Nom. |
|
|
|
|
|
|
Combinations and horse races |
2007-10-28 |
|
From Ian:
How do I calculate the number of combinations for:
Horse races,1 horse in each race.I want all combinations covered.
e.g.5 races, 1 horse in each race. R 1&2, R 1&3,R 1&4, R 2,3,4,5, R 1,2,3,4,5 etc etc.I have worked it out manually to 27 combinations
but if I want to cover more than 5 it will be a big excercise to work out the cost manually.
Many Thanks
Answered by Victoria West. |
|
|
|
|
|
|
A line between 2 vertices |
2007-10-28 |
|
From robert:
what do we call a line between 2 vertices which are not next to each other
Answered by Walter Whiteley. |
|
|
|
|
|
|
Board feet |
2007-10-28 |
|
From Carolyn:
Lumber is measured iin board feet, where a board foot in volume of a piece of lumber one ft sq and one inch thick. How many board feet are in a two by four inch that is 10 feet long?
Answered by Stephen La Rocque. |
|
|
|
|
|
|
For which values of k will k/240 be a terminating decimal? |
2007-10-28 |
|
From Clara:
For which values of k will k/240 be a terminating decimal?
Answered by Stephen La Rocque. |
|
|
|
|
|
|
A car traveled 175m at certain speed |
2007-10-28 |
|
From abdi:
A car traveled 175m at certain speed. if the speed had been 20 mph faster,
the trip could have been made in 1 hr less time. find the speed?
Answered by Stephen La Rocque. |
|
|
