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	A label to cover a plastic cup		2012-10-23
		From Kevin: I'm trying to make a label to cover the entire outer area or a plastic cup. I know there must be a way to figure out the dimensions needed, but I can't seem to figure it out. The circumference of the bottom of the cup is 21.4cm and the circumference at the top of the cup is 29.8cm. The cup is 14.5cm tall. What should the height of the arc from the plane connecting the two ends of the 21.4cm arc. I attached a diagram where x is the value I'm looking for. I'm guessing there is some simple relationship between the length of a line and the arc needed to turn that line into a perfect circle, but I don't know what it is. Can you figure this out and share it with me? Thanks. -Kevin Answered by Penny Nom.
	Differentiation rules		2012-10-23
		From Morgan: Use the derivative rules to differentiate each of the following: 1. f(x)=1/x-1 2. f(x)= sqrt(x) Answered by Penny Nom.
	Some 6 digit numbers		2012-10-23
		From Mason: How many different 6 digit numbers can you make using the digits 1 ,2 5, 6, 7, and 9? How many of these six-digit numbers are divisible by 6? Answered by Penny Nom.
	A 2 acre plot		2012-10-22
		From bob: If a plot of land on the south side is 290.16 feet wide, how many feet on the west and east side to the north to make a 2 acre plot? Thank You Bob Answered by Penny Nom.
	Two swimmers		2012-10-22
		From Emily: Two swimmers start from opposite sides of the pool. Each swimmer swims the length of the pool and back at a constant rate. They pass each other for the first time 40 feet from one side of the pool and for the second time 45 feet from the other side of the pool. What is the length of the pool? Answered by Penny Nom.
	Solving for a/b		2012-10-21
		From Jenny: If a + 3b is equal to 175% of 6b, what is the value of a/b? Answered by Penny Nom.
	Converting a fraction to a decimal		2012-10-20
		From A Teacher: My students want an easy way to convert a fraction to a decimal, can I get one from you? Answered by Penny Nom.
	Two congruent circles in a rectangle		2012-10-20
		From Alexander: Have you ever solved a problem, in which you have a rectangle, from which you need to cut the largest two circles of equivalent diameter? I bisected a rectangle diagonally, but the circles, while tangent to two of the sides, are not tangent to eachother. Can you devise a method for two equivalent circles, that are tangent to two sides, are also to eachother? Take for example a piece of paper, Each if the two largest circles has a diameter that is greater than the distance to the midpoint of the diagonal bisector of the rectangle. Answered by Chris Fisher.
	A proof by contraposition		2012-10-19
		From Rahul: I am not able to understand the following, To prove that if for all e>0, |x|0, then |x|>=e. I understand the approach very well but I do not understand why if |x|=e then |x|>=e. If it is so then why not |x|= Thanks in advance!' Rahul. Answered by Penny Nom.
	A function with 3 asymptotes		2012-10-19
		From rimoshika: find a function that have 3 Asymptotic : y=x/y=sinx/x=-1 Answered by Penny Nom.
	Whites and Sulphurs butterflies		2012-10-19
		From Arlene: The Whites and Sulphurs are one major family of butterflies. There are about 720 varieties. Eleven times more Whites and Sulphurs live outside North America, mostly tropical Asia and Africa, than live inside North America. How many of this family of butterflies live in North America? How many live in the rest of the world? Answered by Penny Nom.
	The nth term of a sequence		2012-10-19
		From Emily: I don't understand how to do this question: Nth term for 9, 7, 5, 3, 1 Is there a fast way to do nth term for this question? Or in fact any question? Answered by Penny Nom.
	Revolutions per second		2012-10-18
		From Crystal: Suppose a car wheel is 26 inches in diameter. a) If the tire completes one rotation, how far would the car travel? b) If the car is traveling at 60 miles per hour, how fast is the car wheel spinning in revolutions per second? Answered by Penny Nom.
	Passing out graph paper		2012-10-18
		From Andrea: mr karnowski has a stack of 125 sheets of graph paper.He is passing out g sheets to each of his students. What is the expression for the number of sheets he will pass out to the first 5 students? Answered by Penny Nom.
	Percentiles		2012-10-17
		From Kenneth: Question from Kenneth: Hello: What is a common calculation used to determine percentiles? For example, five employees have the following salaries: Office worker 1 - $25,000 Office worker 2 - $27,000 Office worker 3 - $30,000 Office worker 4 - $32,000 Office worker 5 - $35,000 What is the percentile rank of office worker 3 who earns $30,000? Here's what I know: Add the number of salaries. Total: 5 Add the smallest number of salaries less than $30,000. There are two. Now, divide 2 by 5 and multiply by 100. 2/5 * 100 = 40 I think the office worker making $30,000 is in the 40th percentile. and I'm not sure what this ranking indicates. I thank you for any helpful reply and or different calculation. Answered by Harley Weston.

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