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Two bus routes |
2010-02-03 |
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From kiyah:
from 4:30 pm to 6:30 pm the route 1 bus stops every 12 min at the gym's bus stop. the route 2 bus stops there every 15 min. if both buses are now at the stop and schedule is kept, how long will it be before both buses will be at the stop again?
Answered by Penny Nom. |
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A snail on an elastic band |
2010-02-03 |
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From Joe:
A snail starts crawling from one end along a uniformly stretched elastic band. It crawls at a rate of 1 foot per minute. The band is initially 10 feet long and is instantaneously and uniformly stretched an additional 10 feet at the end of each minute. The snail maintains his grip on the band during the instant of each stretch. At what points in time is the snail
(a) closest to the far end of the band, and
(b) farthest from the far end of the band?
Answered by Robert Dawson. |
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A piece of string 8 inches long is cut in two pieces |
2010-02-02 |
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From Susan:
If you have a piece of string 8 inches long and cut it in two pieces. Then take the pieces and forms
each into a square such that the area of each squares added together equals 2. How long are the
sides of the squares?
Susan
Answered by Penny Nom. |
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Scale factor |
2010-02-02 |
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From Darlene:
A towers actual height is 300m. An architect makes a scale drawing using a scale factor of 0.0001
A) how tall is the tower in the drawing?
B) if the drawing was 4cm high, what would the scale factor be?
Answered by Penny Nom. |
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1/a + 1/b + 1/c < 1 |
2010-02-01 |
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From Mrityun:
suppose a,b and c are natural numbers such that 1/a + 1/b + 1/c < 1. Prove that
1/a + 1/b + 1/c < = 41/42.
Answered by Penny Nom and Claude Tardif. |
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The area of a hexagon |
2010-02-01 |
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From Vicki:
I need to find out the area of a hexagon (please explain thoroughly; I'm not the best at math) and why/how that particular formula works.
Also, it would be nice if there was an example question with a series of steps (as in not just finding the area and being given the information to do so) that involved both the perimeter and area of a hexagon.
Answered by Robert Dawson and Harley Weston. |
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Everything in a cube 2 miles long? |
2010-01-31 |
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From Naresh:
in a book, i got to read this :
Is it possible to pack the entire population of earth and everything that was created by
humankind in a cube whose edges are 2 miles long ?
Is it possible? Thanks.
Answered by Stephen La Rocque. |
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The height of a roof |
2010-01-31 |
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From carl:
Width of my roof I am building is 5M at baseline, and the pitch is 40%.
What will the height be, and how can I work this out in the future.
Answered by Penny Nom. |
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An impossible isosceles triangle |
2010-01-31 |
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From Hailey:
An isosceles triangle has one angle that measures 50 degrees and another that measures 70 degrees. Why can't this triangle be drawn?
Answered by Penny Nom. |
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A 3D cardboard cupcake |
2010-01-30 |
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From Margaret:
Hi,
I'm an art student and I'm attempting to build a 3D cupcake out of cardboard.
I want it to have a circular base of 8.5 inches and sides that are 7'' tall and slope outward so the top of the base is 29'.
The top with the frosting would be a detachable lid made from a cone with a base circumfrance of 29".
My problem is how to cut the side so they will slope out, I'm pretty sure there needs to be a curve, however I don't how to calculate the degree of it.
Ideally I want the sides to be a single piece of cardboard.
I also don't know how to calculate the arc needed to make a cone who's circular base's circumfrence is 29''.
Thanks,
Margaret
Answered by Stephen La Rocque. |
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A decrease in travel time |
2010-01-30 |
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From Mike:
if a 100 mile trip averages 50 miles per hour, how much distance does one need to travel at 90 miles per hour to decrease travel time by 10%
Answered by Stephen La Rocque. |
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Aggregate must for a road base |
2010-01-30 |
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From Bryan:
How many cubic yards of aggregate must be ordered for a road base 16 in. thick and 2 miles long with a top width of 30 ft, if the side slopes are one on one, or 45 degrees
Answered by Stephen La Rocque. |
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An integral |
2010-01-29 |
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From amr:
find the value of the following integral:-
(1+x)power (-1/2) dx
Answered by Robert Dawson. |
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1^3 + 2^3 + 3^3 +4^3 ... n^3 = ? |
2010-01-29 |
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From ireimaima:
Hi..
Can u please help me with this question..
I find that when i test eg: n=2 for n (n+1) /4,
it seems that it does not giving me the right answer of 1^3 + 2^3 = 9
but 3/2... i'm confuse..can u please help me..thanks so much
Prove that:
1^3 + 2^3 + 3^3 +4^3………………………………..n^3 = n (n+1) /4
Answered by Penny Nom. |
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Is it a square? |
2010-01-29 |
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From Manick:
I have a question. how to find whether a given integer is a perfect square or not?
Answered by Robert Dawson. |
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