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	A 3 by 3 block on a calendar		2006-01-18
		From A student: Choose two different blocks of nine numbers arranged 3 across and 3 down on a calendar, and check that this rule holds: For any block of nine numbers the average of the four corner numbers is equal to the middle number. Show your work and explain why the rule works. Answered by Penny Nom.
	I need to order sand for playgrounds		2006-01-18
		From Jody: I need to order sand for playgrounds. I have their square footage and the various depths of sand needed for each, but sand comes in tons. What is the formula for converting square footage and depth to tons (for example: 6 inches of sand needed for a 200sq ft area = how many tons?) Answered by Penny Nom.
	The centroid of a triangle		2006-01-18
		From Andrea: I am trying to find the centriod of a triangle. I have been given the three vertices of the triangle: A (-25, -20), B (-5, -40), and C (15, 30). I believe I calculated the correct midpoints: AB(E) (-5, 5), BC(D) (5, -5), and AC(F) (-15, -30). When I graphed these points I came up with the solution (-5, -10), but I can't seem to write the answer out (equations of the lines, etc) correctly. Any help would be greatly appreciated! Answered by Penny Nom.
	What are math arrays?		2006-01-18
		From Jeff: What are math arrays? Answered by Penny Nom.
	Interior and external angles of a polygon		2006-01-17
		From Anthony: In a regular polygon, the ratio of the interior angles to the exterior angles is 3:1. (a) Find the measure of the interior angle. (b) How many sides are there Answered by Penny Nom.
	A sequence of circles and tangents		2006-01-16
		From Paul: Consider a circle whose center is (2,2) and whose radius is 1, and the straight line that goes through the origin and that is tangent to this circle so that the intersection between them is as shown in the attached picture. With this new point we make a new circle whose radius is half of the first one, and we calculate the corresponding intersection point with the same suppositions as in the first case. We repeat the process to the infinite. Find the distance between the center of the circle in the infinite and the origin (point (0,0)). Answered by Chris Fisher.
	The height of a triangle from the lengths of the sides		2006-01-16
		From A student: How do you figure out the height of a triangle when all you have is the length of the sides of the triangle? Answered by Claude Tardif.
	Intercepts and slope		2006-01-15
		From Anthony: Given -1.7x + 0.8y=7.1: (a) state the intercepts and slope for the graph (b) Draw the graph Answered by Penny Nom.
	51 acres		2006-01-15
		From A landowner: i just wanna know how many miles are surrounding my 51 acres? a simple answer will do. thanks:) Answered by Penny Nom.
	Polar to Cartesian coordinates		2006-01-15
		From Linden: How do you convert six units at 30 degrees Polar Coordinate into a Cartesian Coordinate? Answered by Penny Nom.
	Percentage discount		2006-01-15
		From Louise: Avril is buying a computer. She finds two places with a discount."Classy Computing" is selling a computer that was £650 and NOW it has £50 off. "WWW.CHEAPO.COM" is also selling a computer that is £650 but it NOW has 10% off. WHICH IS CHEAPER? Answered by Penny Nom.
	12100 sq ft is how many acres?		2006-01-14
		From Sydney: If there are 12100 Sq. Ft in property what would that be acre wise? Answered by Penny Nom.
	Who is lying?		2006-01-14
		From Diane: A business man was working in his home office when he realized he had left a five-dollar bill in the book he had been reading. He called his butler to bring him the book from the library. When he got the book, the bill was no longer there. He then questioned the maid and the butler. The maid remembered seeing the bill between pages 99 and 100 in a book to the left of a business book. The butler did not recall seeing the bill, but was sure the book was to the right of the business book, because to the left of it there was a statistics book. Who is lying? Answered by Penny Nom.
	Concrete tubes		2006-01-14
		From Paul: I have 15 tubes. Each tube measures 12in.x 48in. I have to fill each one with concrete. How do I figure how many cubic yards of concrete I will need? Answered by Penny Nom.
	What initial velocity is required to double the maximum height		2006-01-14
		From A photographer: A body is thrown into the air with an initial velocity V ft./sec. What initial velocity is required to double the maximum height previously obtained? Answered by Penny Nom.

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