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Grade 5 shapes and measurements |
2007-09-23 |
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From Marina:
I'm helping my grade 5 son in this assignment but I don't know how. There are 2 question I would like you to help me:
1.How can the shapes used to form a larger similar figure using 4 shapes: ( a 3 by 3square is drawn in a 6 by 6 dot figure,drawing attached)
2.You are planning to build a birdhouse measurement is attached,. You are going to cut the pieces from a board that is 12 inches wide. How long should the board be?
Answered by Penny Nom. |
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The weights of packages are normally distributed |
2007-09-23 |
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From alan:
the weight of a packet of sweets produced in a factory are normally distributed.
the mean weight is 100g
the standard deviation is 2g
all packets weighing less than 99g and more then 105g are rejected
what proportion are rejected
Answered by Penny Nom. |
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The diagonal of a square |
2007-09-23 |
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From Nasreen:
A(7,2) and C(1,4) are two vertices of a square ABCD
find in the form ax+by=c the equation of the diagonal BD
Answered by Stephen La Rocque. |
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12 men can complete a work in 8 days |
2007-09-23 |
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From farah:
12 men can complete a work in 8 days. 3 days after they started working, 3 more men joined. In how many days will all of them together complete the remaining work.
Answered by Stephen La Rocque. |
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Are the diagonals of a trapezoid ever perpendicular? |
2007-09-23 |
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From Amanda:
Are the diagonals of a trapezoid ever perpendicular?
Answered by Harley Weston. |
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The sequence 2,4,7,11,16,22 |
2007-09-22 |
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From Simon:
I thought i understood how to explain how to work out the nth term on a
sequence of numbers until my son had this sequence to work out -
2,4,7,11,16,22
We have worked out the 2nd differance is +1 but nothing else seems to fit.
Im sure the answer is staring us in the face but cant see the wood for the
trees!
Answered by Denis Hanson and Steve La Rocque. |
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Sample variance and population variance |
2007-09-22 |
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From Willy:
I have a question in sample variance and population
my name is Willy
the question in the attached file...
Answered by Harley Weston. |
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Finding equations, intersection point of two lines at right angles |
2007-09-22 |
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From Yaz:
Find the equation of the line joining A(-1,-9) to B(6,120). Another line passes through C(7,-5) and meets AB at rigth angle of D. Find the euation of CD and calculate the co-ordinates of D.
Answered by Stephen La Rocque. |
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The incline of my yard as it slopes away from my house |
2007-09-22 |
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From Janet:
I need to calculate the degree (or is it percent?) of incline of my yard as it
slopes away from my house. Do I visualize a right angle formed by a
level line from the bottom of the slope to the side of the house, and then
compare the line of the slope against the right angle to get the degree?
Or is an incline calculated by the measurement of the rise in 100 feet? For
instance, if the ground rises 3 feel in a distance of 100 feet, is that a 3%
incline? And if it rises 4 feet in a distance of 25 feet, is that a 16% incline?
Thanks so much.
Answered by Stephen La Rocque. |
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Two equations in two unknowns |
2007-09-22 |
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From Mary:
Having problems doing this problem, looking for a solution with the work. I would like to see how you got your answer, to see what I was doing wrong.
solve using the substitution method, is there "no solution" or "infinitely many solutions"
4x+y=4
2x+8y=0
Answered by Stephen La Rocque and Leeanne Boehm. |
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How much water to fill my bedroom? |
2007-09-22 |
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From hector:
how can i find out how much water i can fill my bedroom with when it measures 12 ft.x12 ft.x10 ft.
Answered by Steve La Rocque and Penny Nom. |
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The derivative of f(x)=1/(x-1) |
2007-09-21 |
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From Michelle:
im having trouble finding the derivative of f(x)=1/(x-1) using the f(x+h)-f(x)/h method.
Answered by Stephen La Rocque. |
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Cubes |
2007-09-21 |
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From Yvonne:
The numbers 756 and 72, expressed as products of prime factors, are 756 = 2² x 3³ x 7 and 72 = 2³ x 3²
Use these result to find,
the smallest integer, x, such that 756x is a perfect cube.
Answered by Penny Nom. |
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Working together |
2007-09-21 |
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From farah:
A can do a piece of work in 10 days while B can do the same work in 15 days . They work together for 5 days and the rest of the work is done by C in 2 days . If they get 400$ for the whole work , what should be A's share.
Answered by Harley Weston. |
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Water flowing into a tank |
2007-09-21 |
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From andrew:
Hi, I've been having real trouble visualizing this problem as apposed to a conical tank.
It says the base of a pyramid-shaped tank is a square with sides of length 12 feet. The
vertex of the pyramid is 10 feet above the base. The tank is filled to a depth of 4 feet, water is flowing
into the tank at the rate of 2 cubic feet per minute. Find the rate of change of the depth of water in the tank.
Answered by Harley Weston. |
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