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Sand falling off a conveyer |
2010-04-02 |
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From Katherine:
sand is falling off a conveyer onto a pile at the rate of 1.5 cubic feet per minute. The diameter of the base is approximately twice the altitude. At what rate is the height of the pile changing when it is 10 feet high?
Answered by Penny Nom. |
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Pyramids and parallelograms |
2010-04-01 |
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From Vivi:
Hi, my name is Vivi, and math teacher is giving a geometry test. I tend to forget how to find the surface area and volume of triangular pyramids and parallelograms. Do you have a way of remembering how to find the surface area?
Answered by Harley Weston. |
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A ratios problem |
2010-04-01 |
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From Jules:
1a) If 2/3 of the boys and 3/4 of the girls at a party are dancing, what is the
ratio of boys to girls, if all the dancing couples consist of a boy
and girl?
b) If the total number of the boys and girls of the party is 153, how
many boys are at the party?
Answered by Penny Nom. |
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Total tax |
2010-03-31 |
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From Keli:
if the gst in Ontario is 5% and the pst is 8% the total tax would be 13%. How come the total tax is 1.13? Shouldn't it be 0.13?
Answered by Robert Dawson and Tyler Wood. |
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1/1+1/2+1/3... |
2010-03-31 |
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From Mohd:
you explained the way of getting the summation of 100 series numbers
but what is the summation of the numbers 1/1+1/2+1/3+1/4+1/5.............................+1/100
Answered by Robert Dawson. |
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Tiling a floor |
2010-03-31 |
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From shane:
a floor in a house is 12'6" in width and 10'4" in length. Tiling the floor with each tile 5" on each side. First express the square footage into an improper fraction. Second express the area of each tile in square feet. Third how many tiles needed to tile the floor. Fourth explain how answers relate to real world
Answered by Harley Weston. |
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The diagonals of a rectangle |
2010-03-30 |
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From Tabatha:
The diagonals of a rectangle are 8 units long and intersect at a 60 degree angle. Find the dimensions of the rectangle.
Answered by Penny Nom. |
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A system of equations |
2010-03-30 |
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From samantha:
the equations of two lines are 6x-y=4 and y=4x +2.what is the value of x in the solution for this system of equations?
Answered by Penny Nom. |
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A 25% discount |
2010-03-29 |
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From Susan:
If something costs 1.00/per lb. and that price includes a 25% discount. How do you calculate what the price was before the discount?
Answered by Penny Nom. |
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Sample size |
2010-03-29 |
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From Rae:
What sample size was needed to obtain an error range of 2% if the following statement was made? "75% of the workers support the proposed benefit package. These results are considered accurate to within + or - 2%, 18 out of 20 times. This seems like a straight forward question but I'm getting it wrong. Could you please help me out even just the set up would be appreciated so I can see if that's where I'm going wrong. Thanks
Answered by Harley Weston. |
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The sides of a 30-60-90 triangle |
2010-03-29 |
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From maris:
Find the sides of a 30-60-90 triangle whose perimeter is 6. The solution must use systems of equations using 3 variables.
Answered by Penny Nom. |
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The perimeter of a lake |
2010-03-29 |
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From Bill:
I am trying to figure out the approx. perimeter of a 22 acre lake. Can I solve this by calculating the sq. ft. in 22 acres and then take the square foot to find out the sides of a 22 acre square and then add the sides together to get the perimeter?
Answered by Penny Nom. |
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The area of a polygon |
2010-03-28 |
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From John:
Question from John, a student:
How do you find the area of a polygon with any given amount of sides?
Answered by Harley Weston. |
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A trig identity |
2010-03-27 |
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From Anne:
Prove:
(2tanx-sin2x)/2sin^2x=tanx
Answered by Penny Nom. |
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Coins in 3 parking meters |
2010-03-27 |
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From Zena:
There are 227 coins altogether in 3 parking meters.
The second meter has 37 more coins than the first meter.
The third meter has twice as many coins as the second.
How many coins in each meter?
Answered by Penny Nom. |
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