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	Prove that the set of all positive odd integers is an infinite set		2009-06-20
		From Nazrul: How can I prove that the set of all positive odd integers is an infinite set. Thank you in advance. Answered by Victoria West.
	What is 3 trillion divided by 3 billion?		2009-06-18
		From Dianna: What is 3 trillion divided by 3 billion? Answered by Penny Nom.
	Maximum Volume of a Cylinder Inscribed in a Sphere		2009-06-18
		From Jim: Hello I have a hard time finishing this question: A right circular cylinder has to be designed to sit inside a sphere of radius 6 meters so that each top and bottom of the cylinder touches the sphere along its complete circular edge. What are the dimensions of the cylinder of max volume and what is the volume? Answered by Janice Cotcher.
	Mowing 17 lawns		2009-06-18
		From kevin: I need help setting up a equation to solve the following question: If a gardener can mow 3 lawns in 7 hours, how long should it take him to mow 17 lawns. I can solve the problem, but I don't know how to set up the equation. Answered by Penny Nom.
	Two questions from math class		2009-06-18
		From Con: Hello, My name is Con and my son is required to answer the following questions for his maths class. He has attempted Q1 through trial and error and has found the answer to 72453. Is this correct? He has attempted to draw the triangles described in Q2 in a number of ways and has found that BE can not equal ED and is dependent of angle BAC. Therefore, he claims that the triangle can not be drawn/practical. Is this correct or is there a slolution? Q1. Digits 2, 3, 4, 5 and 7 are each used once to compose a 5-digit number abcde such that 4 divides a 3-digit number abc, 5 divides a 3-digit number bcd and 3 divides a 3-digit number cde. Find the 5-digit number abcde. Q2. Let ABC be a triangle with AB=AC. D is a point on AC such that BC=BD. E is a point on AB such that BE = ED = AD. Find the size of the angle EAD. Con Answered by Chris Fisher.
	The integral of x^x		2009-06-18
		From ANGIKAR: what would be the integration of (X^Xdx)? give answer in details. Answered by Robert Dawson and Harley Weston.
	Successive differences		2009-06-18
		From Jonathan: I'm trying to find the next number sequence for this equation: 1 11 35 79 149 251, my problem is that I worked it out and ended up with a single number 17. What am I doing wrong. Thank you for any help. Answered by Robert Dawson and Penny Nom.
	Thermal Expansion of Steel		2009-06-17
		From Ken: Hi there, We are rollforming steel roofsheeting in 65M lengths and the = question of linear expansion has cropped up.I would like to know what = the expansion rate of this sheet would be over a temperature rise of say = 40degree F.in mm per Meter or whatever the norm is. The sheet is 0.53mm = thick and is 700mm in width,I hope this is sufficient info to enable you = to do your calculation.Many thanks, in anticipation. Ken Answered by Janice Cotcher.
	Divisibility		2009-06-17
		From Sophia: Hello Please help my son with the solutions to the following: a) Determine the remainder when 2^2009 + 1 is divided by 17; b) Prove that 30^99 + 61^100 is divisible by 31; c) It is known that numbers p and 8p^2+1 are primes. Find p. Again, your assistance is greatly appreciated. Thanks Sophia Answered by Robert Dawson.
	The smallest 4 digit number		2009-06-17
		From Kat: What is the smallest 4 digit number? 0001 or 1000 Answered by Robert Dawson.
	A difference quotient		2009-06-17
		From Sue: When s(x)=x^3+x, compute and simplify the difference quotient s(x+h)-s(x)/h. Answered by Harley Weston.
	Completing the square		2009-06-16
		From rebecca: Find the roots of the equation by Completing the square. Express your answer in exact form and in decimal form to 2 decimal places. a) x(squared)+10x+23 b)3y(squared)+12y+3 Answered by Stephen La Rocque.
	Factoring a quadratic		2009-06-16
		From Rebecca: solve the quadratic equation by factoring. a) x(squared)+7x+10=0 Answered by Stephen La Rocque.
	Triangular Numbers		2009-06-16
		From Chinonyerem: Question from Chinonyerem, a student: Each of the numbers 1 = 1, 3 = 1+2, 6 = 1+2+3, 10 = 1+2+3+4 ,... represents the number of dots that can be arranged evenly in an equilateral triangle:                             .                   .        . .         .         .       . . .             ... .      . .      . . .    . . . . This led the ancient Greeks to call a number TRIANGULAR if it is the sum of consecutive integers, beginning with 1. Prove the following facts concerning triangular numbers: (a) A number is triangular if and only if it is of the form n(n+1)/2 for some n >= 1 (b) The integer n is a triangular number if and only if 8n+1 is a perfect square (c) The sum of any two consecutive triangular numbers is a perfect square (d) If n is a triangular number, then so are 9n+1, 25n+3, and 49n+6 Answered by Penny Nom.
	Subsets		2009-06-16
		From Tracy: Suppose C is the subset of D and D is the subset of C. If n(c)=5, find n(D) What other relationship exists between sets C and D? Answered by Penny Nom.

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