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Numbers or Percentage or probability or what? |
2009-01-07 |
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From Chew:
Teacher A teaches 50 students and 45 of them obtained straight As.
Teacher B teaches 5 students and 5 of them obtained straight As.
Which teacher would you send you child to and why?
Answered by Robert Dawson and Harley Weston. |
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An area of 64cm squared and a perimeter of 64 cm. |
2009-01-07 |
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From Dale:
i need to draw an object that has an area of 64cm squared and a perimeter of 64 cm. Can you help me out......
Answered by Robert Dawson. |
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The area of a region bounded by two curves |
2009-01-07 |
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From Rogerson:
Find the area, S, enclosed by the given curve(s) and the given line.
y = x^2 - x - 1, y = x+2
Answered by Harley Weston. |
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A union B and A intersect B |
2009-01-07 |
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From Jim:
Suppose A and B are sets and (A union B) = (A intersect B). Is it true that A=B.
Answered by Penny Nom. |
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The volume and surface area of a sphere |
2009-01-07 |
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From destini:
the volume of a sphere is equal to its surface area. what is its radius
Answered by Chris Fisher. |
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30% profit |
2009-01-06 |
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From bob:
this is a basic question that I just can't get thru my head.
I know all my cost for a product, if I want to sell at a given profit can I divide by a given
number, example for 30 % divide by .7 or do I multiply?
Is there a simple answer for this? Sure would make my work a lot easier.
Thank you for your time
Puzzled in Ohio
Answered by Penny Nom. |
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A kennel with 3 individual pens |
2009-01-06 |
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From Jean:
An animal clinic wants to construct a kennel with 3 individual pens, each with a gate 4 feet wide and an area of 90 square feet. The fencing does not include the gates.
Write a function to express the fencing as a function of x.
Find the dimensions for each pen, to the nearest tenth of a foot that would produce the required area of 90 square feet but would use the least fencing. What is the minimum fencing to the nearest tenth?
Answered by Harley Weston. |
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Filling a round hole |
2009-01-06 |
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From Kathy:
I need to fill a hole that is 24 feet round x 12 inches deep. How much dirt will I need?
Answered by Robert Dawson. |
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The factors of an integer |
2009-01-06 |
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From Madison:
what are the factors of 878
Answered by Robert Dawson. |
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Un volume d'une capacité minimal |
2009-01-05 |
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From Pauline:
je doit faire un volume d'une capacité minimal de 2500 cm 3 en quell matiere que ce soit
* un prisme a base pentagonale non réguliere
* une sphere
* stella octangula
Answered by Pierre-Louis Gagnon. |
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Trig identities |
2009-01-05 |
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From Michael:
1) Determine if the following is an identity. If it is, prove it, If it isn't state it.
tan x + cot x = sec x * csc x
and
1 - (cos^2) x = 1+ (cot^2) x
Answered by Robert Dawson and Harley Weston. |
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y varies jointly as x and the square of z and... |
2009-01-05 |
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From peter:
I don't really get the terms in this problem. Could you explain it: If y varies jointly as x and the square of z and inversely as the cube of w, by what factor is y increased when z is doubled and w is divided by 3 and x remains the same?
Answered by Harley Weston. |
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A 4-digit number |
2009-01-05 |
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From Anya:
It is a 4-digit number
The tens are double the ones.
The thousands are double the tens.
The sum of the digits is 19.
What number is it?
Answered by Penny Nom. |
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The area enclosed by a curve and the x-axis |
2009-01-04 |
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From Rogerson:
Find the area, S, enclosed by the curve y = -x^2 + 6x - 5 and the x-axis in the interval 0≤x≤4.
Answered by Harley Weston. |
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Determine y'' by implicitly differentiating twice |
2009-01-04 |
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From Walter:
Given x^3 - 3xy + y^3 = 1 , determine y'' by implicitly differentiating
twice. I cannot solve this. Would you be kind enough to perform the
mathematics and show the steps involved in obtaining the solution?
Answered by Harley Weston. |
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