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	Odd plus even is odd		2001-10-14
		From James: Why is the sum of an odd number and an even number always odd? Answered by Peny Nom.
	Area of a quilt		2001-10-14
		From Jack: how would you find the area of the quilt? which is a square how would you fined the area of each square? Answered by Penny Nom.
	Theme day		2001-10-14
		From A teacher: I woulld like a math theme for a theme day in a high school, grades 9-12. Our last theme was fractal fest. Answered by Penny Nom and Claude Tardif.
	Maximize the area		2001-10-13
		From Mike: I have no clue how to do this problem. Here is what the professor gave to us: A=LW C=E(2L+2W) + I(PL) Where P = # of partitions E= cost of exterior of fence I = cost of interior of fence C = total cost of fence . . . Answered by Harley Weston.
	Mathematical & conventional meaning of a word		2001-10-12
		From A student: What is the mathematical & conventional meaning of a word? Like the word Rational or Median. Answered by Penny Nom.
	60 seconds in a minute		2001-10-11
		From Andy: I am a fourth grade teacher. Yesterday my students asked "Why are there 60 seconds in a minute?" Which also led to 60 minutes in an hour? I have had trouble determining why the number 60? Any help would be appreciated. Answered by Penny Nom.
	4 sinx cosy = 1		2001-10-10
		From A student: How would i differentiate the following example in terms of t (x and y are functions of t) 4 sinx cosy = 1 Answered by Claude Tardif.
	Acres		2001-10-10
		From Allison: how many feet are there in an acre? Answered by Chris Fisher.
	eix = cosx + isinx		2001-10-10
		From Peter: Given: eix = cosx + isinx substitute -x for x to find e-ix, simplifying your answer use the given and part a to find an identity for cosx making no reference to trig functions find an identity for sinx . . Answered by Penny Nom.
	When will the ship disappear?		2001-10-10
		From Stacy: If the sail of a ship were a 100 ft. tall and you were a mouse at the edge of the shore looking out at it, how far out would the ship be when it disappears? ( your eye level is level with the water.) Answered by Harley Weston.
	Ratio and proportion		2001-10-10
		From Steve: Where would you use a proportion and/or a ratio in a real life job or problem. Answered by Leeanne Boehm and Walter Whiteley.
	Six nines		2001-10-09
		From A mom: My middle schooler (sixth) has to calculate the integers 0-20 using only 6 nines. We have done all but the integer 14. He can not use decimals or double the nine like 99 or 19. the fraction 9/9 is okay. Keep in mind of course the order of operations. Answered by Claude Tardif.
	Pythagoras & magic squares		2001-10-09
		From John: My grandson became intrigued when he recently 'did' Pythagoras at elementary school. He was particularly interested in the 3-4-5 triangle, and the fact that his teacher told him there was also a 5-12-13 triangle, i.e. both right-angled triangles with whole numbers for all three sides. He noticed that the shortest sides in the two triangles were consecutive odd numbers, 3 & 5, and he asked me if other right angled triangles existed, perhaps 'built' on 7, 9, 11 and so on. I didn't know where to start on this, but, after trying all sorts of ideas, we discovered that the centre number in a 3-order 'magic square' was 5, i.e. (1+9)/2, and that 4 was 'one less'. Since the centre number in a 5-order 'magic square' was 13 and that 12 was 'one less' he reckoned that he should test whether a 7-order square would also generate a right-angled triangle for him. He found that 7-24-25, arrived at by the above process, also worked! He tried a few more at random, and they all worked. He then asked me two questions I can't begin to answer ... Is there a right-angled triangle whose sides are whole numbers for every triangle whose shortest side is a whole odd number? and Is each triangle unique (or, as he put it, can you only have one whole-number-sided right-angled triangle for each triangle whose shortest side is an odd number)? Answered by Chris Fisher.
	Lucas' theorem		2001-10-09
		From Tania: How could I demonstrate: nCp is congruent to floor(n/p) (modulo p)? where rCk is a binomial coefficient, rCk = r(r-1)...(r-k+1)/k(k-1)...1, and p is a prime number Answered by Richard McIntosh.
	Binomial probabilities		2001-10-08
		From Amna: I had a few binomial probability questions which I can not use from the tables as instructed: If 60 % of television viewers are watching a certain program, what is the probability tha tmore than half of those selected in a random sample of five will be watching the specified program? If it is known according to Mendel's Law, that we can expect in teh long run to have 3 white, 1 brown rabbits in every 4 rabbits of a certain type, what is the probability that 2 in a litter of 3 will be white? On the average, 2% of the items sold in a department store are returned for refunds. what is the probability that of its next five items sold, at most two will be returned for refunds? Answered by Leeanne Boehm.

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