Here are the newest items added to Quandaries & Queries:
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	Parking spaces		2000-11-07
		From Lydia: A parking lot has 4 aisles. Each aisle is about 40 yards long and has parking places on both sides. If a parking place is 3 yards wide, how many cars can the parking lot hold? Answered by Penny Nom.
	How many tens are in 400?		2000-11-07
		From A student: How many tens are in 400? Answered by Penny Nom.
	Crown molding mitre cuts		2000-11-06
		From Jim Tomfohrde: My question has to do with making mitre cuts when installing crown molding. Crown molding is the trim that is put up at the top of walls with one edge on the wall and the other edge on the ceiling. To make a mitre cut on your mitre saw for a 90-degree corner you can lay the molding flat on the saw base, set the bevel of the blade to 34 degrees and the mitre to 31.5 degrees (these may be slightly appoximate). Of course depending on which piece of molding you're cutting you will cut one end or the other, or use the left or right end. These angles allow the cuts to line up and form a seamless corner when they're put in place on the wall/ceiling at 90 degrees. My question is this - is there some mathematical formula from which the 34 degrees and 31.5 degrees are derived. I want to know this because in many cases the corner is not 90 degrees but can be more or less, and in these instances I would like to know if I can calculate the bevel and mitre to use based on the angle of the corner. Answered by Harley Weston.
	Graphing F(x) = 3x		2000-11-06
		From Jose: graph the exponential problem F(x)=3x Answered by Harley Weston.
	Banana yogurt		2000-11-03
		From James: A grocery store has 100 cartons of banana yogurt in stock.Each carton contains 12 cup of banana yogurts.The probability that a cup has fewer than 20 banana chunks in it is 10 %. So,What is the probability that between 15 and 25 (inclusive) cartons out of the 100 cartons have exactly 3 cups with fewer than 20 banana chunks? Answered by Harley Weston.
	Expected number		2000-11-02
		From James: 1)There are 40,25,50 students in the traditional,reformed,and reformed traditional Calculas sections taught by three teachers. On one fine day the three sections congregate together to watch the NOVA video tape on Fermat's Last Theorem. a) A student is randomly selected from he crowed of students.What is the expected number of students in the same section of this student? ****this question which i did not have any idea to do as follow for the part b b) If one of the three teachers is selected at random, what is the expected number of students taught by is teacher? Answered by Harley Weston.
	Two problems		2000-11-02
		From Michael: Question: I mistakenly divided a number by 5 when I should have multiplied by 5. FInd my percent of error. Next Question: How many odd numbers are between 10 and 9,999 from the digits 0-9 if each digit is used once per number. Answered by Penny Nom.
	Length of a shadow		2000-11-01
		From Jessy: A man who is six feet tall is walking away from a street light that is fifteen feet tall. How long is the man's shadow when he is ten feet away from the light? Answered by Penny Nom.
	Symmetry		2000-11-01
		From A student: I am a 6th grader look for material on mathametical symmetry . Most of the material I have found is science related . I have to write a paper on this . Any resource info you could lead me to would be helpful. Thank you for your time. Answered by Chris Fisher.
	Perfect numbers		2000-10-31
		From A student: I was wondering if you could help me answer a question my pre-algebra teacher asked in class the other day. He asked if we knew what the perfect numbers where. He told us the first number is 6 the second number is 28 but the third he did not tell us. Do you know what the third perfect number is? Answered by Paul Betts and Chris Fisher.
	Factoring a cubic		2000-10-31
		From A student: Factor Completely 18p3 - 51p2 - 135p Answered by Paul Betts and Penny Nom.
	Lobbing a tennis ball		2000-10-31
		From Alex: If a tennis ball is lobbed into the air with an initial upward velocity of 12 meters per second, its velocity and height will be functions of time in flight described by the following rules: V=12-9.8T and H=1+12T-4.9T 2 Find the maximum height of the tennis ball and the time it takes to reach that height. Answered by Penny Nom.
	False Positives		2000-10-29
		From James: A rare disease infected 1 in 1000 people in the population. A test for the disease is accurate 99% of the time when given to an infected person and also when given to a heathy person. Fill out a two-tier tree diagram and find the probability of the false positive(i.e the conditional probabily of being healty even when tested postive by the test) Comment on the result? ... Answered by Penny Nom.
	Square roots		2000-10-29
		From Pamela: HERE GOES(I WILL USE Q AS THE SYMBOL FOR SQUARE ROOT): 8(Q2) - 5(Q2) + Q2 SECOND PROBELM IS (1 + Q2)2 LAST ONE 3/(2-Q5) Answered by Claude Tardif.
	Overlapping a circle and a square		2000-10-28
		From Jacky: A square with a dimension 20 by 20cm. and a quarter of the circle with the radius of 25cm (A quater of a circle is created by 2 cuts that are perpendicular bisectors of each other where the intersecting point is at the centre of the circle). With these 2 pieces, the 2 pieces are placed over each other in which the 90o angle of the quarter circle matches with one of the right angles on the square. Now, calculate the overlapping area of the 2 figures. Answered by Chris Fisher and Harley Weston.

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