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30 students |
2009-08-06 |
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From Peter:
Question from Peter, a student:
Can you please help with the following questions?
(a) It is known that among any group of the three students in a class two of them are friends. Total number of students is 25. Prove that there is a student who has at least 12 friends.
(b) There are 30 students in a class. They sit at 15 double desks, each one is for two students. Half of the girls sit with boys. Is it possible to make a rearrangement so that half of the boys sit with girls?
Answered by Penny Nom. |
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Exponential form |
2009-08-05 |
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From motaz:
Let x = log_2 1/8 Write the exponential form of the equation and solve the equation for x
Answered by Stephen La Rocque. |
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Susan's RRSP |
2009-08-05 |
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From Polly:
Susan contributed $500 every 6 months for 14 years into a RRSP earning interest @ 7.5% compounded semi-annually. Seven years after the last contribution Susan converted the RRSP into a RRIF which is to pay her equal 1/4 payments for 16 years. If the first payment is due 3 months after the conversion into the RRIF and the interest on the RRIF is 9% compounded 1/4, how much will Susan receive every 3 months?
Answered by Stephen La Rocque. |
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Percentage decrease |
2009-08-04 |
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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. |
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Angular speed |
2009-08-04 |
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From Mary:
The engine of a sports car rotates at 5000 revolutions per minute (rpm). Calculate the angular speed of the engine in radians per second. Use 2 radians = 1 revolution.
Answered by Penny Nom. |
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Tossing a penny 26 times |
2009-08-04 |
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From Basma:
Jack is going ot toss a penny 26 times.
How many times should it land on heads?
Answered by Robert Dawson. |
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A spherical dome |
2009-08-03 |
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From Eric:
I have recently been asked to resurface a dome sculpture for my local council but i'm having problems working out the area. Here are the dimensions.
The height of the dome is 3m from the ground to the top of the arc. The arc itself from the ground rising up to the 3m point and back down, is 10m. The dome is 7m wide from one side to the other through the centre, at ground level.
I hope there is enough detail here. It's been a long time since i was in a maths class.
Thank you, hope to here from you soon!
Answered by Stephen La Rocque. |
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I expect to retire in 12 years |
2009-08-03 |
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From Polly:
I expect to retire in 12 years. Beginning one month after my retirement, I would like to receive $500 a month for 20 years. How much must I deposit into a fund today to be able to do so if the rate of interest on the deposits is 12% compounded monthly?
Answered by Stephen La Rocque. |
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HCF |
2009-08-03 |
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From Nazrul:
If (x+ a) be the H,C.F. of x^2+px+q and x^2+mx+n, prove that (p-m)a=q-n
Answered by Stephen La Rocque. |
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Math in everyday life |
2009-08-03 |
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From Naveen:
Dear sir,
We are advised to do a project on "Mathematical modeling to solve various problems
of our everyday life/environmental related problems...... Can u plz help us by mailng some
ideas, suggestion,reference to make my project successful.... Thanking you......
Waiting for your favourable reply......
Answered by Penny Nom. |
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Two circles |
2009-08-03 |
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From Karan:
We are given 2 circles with radii 12cm and 3 cm. We have to find AB
Answered by Penny Nom. |
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A cone with the top cut off |
2009-08-02 |
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From Paul:
I am making a cone with a diameter of 1300, a base of 500, a side length
800. I need to workout so I can draw it out flat, cut it out, and make into
a cone.
Answered by Harley Weston. |
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A walkway around a flower garden |
2009-08-01 |
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From Barbara:
A rectangular flower bed measuring =C2=A0 10 feet by 15 feet =C2=A0 has a surrounding walkway on all sides that measure 186 square feet. How wide is the walkway?
Answered by Harley Weston. |
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root 2 is irrational |
2009-07-31 |
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From prateet:
prove that root2 is an irrational number.
Answered by Robert Dawson. |
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Fencing five acres |
2009-07-31 |
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From Aaron:
Ok So I need to order fencing for my property I have 5 acres and would
like to fence in the perimeter, I cant for the life of me figure out how
many feet of fencing to order for help please im an idiot.
Answered by Robert Dawson. |
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