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	The area of my lot		2003-01-07
		From Linda: I have a lot that is 210 feet in the front, 240 feet in the back and the sides each measure 150 feet. How many square feet is this all together and how close to an acre is it? Answered by Penny Nom.
	Integration of 1/(2+cos(x))		2003-01-07
		From A student: integral from pi to 0 of dx/(2+cos x) i used the substitution t=tan(x/2) and i ended up with integral from +infinity to 0 of 2dt/(t2+3) which looks like an inverse tan function , and i ended up with sqr(27)/2 pi , which is not the same as my calculator's answer , so i suspct i am doing some thing wrong. can some one tell me where i am going wrong please. Answered by Penny Nom.
	des conversions de bases différentes		2003-01-04
		From Christian: Je cherche désespérément la (les) règle(s) pour réussir des conversions de bases différentes : de base x vers base y. Answered by Claude Tardif.
	Mean and median		2003-01-04
		From Jan: I have a question re: mean and median. I know what the difference is but just need some clarification on when you would use the mean and when you would use the median. Isn't it the case that with a skewed distribution the average (mean) would be higher or lower than the median, but with a normal distribution they would be very similar values? If you have any examples to help explain this that would be greatly appreciated. I am a teacher (of sorts!) and the person who is asking me the question is actually my boss! Answered by Penny Nom.
	Constructions of polygons		2003-01-03
		From Garrett: Our teacher just finished the constructions unit, and he mentioned briefly about odd sided figures such as pentagons and septagons, only that they're very hard. My question is, how do you draw, with a compass and a straight edge, a pentagon and septagon? Answered by Chris Fisher.
	Two numbers have a ratio of 5:3		2003-01-01
		From Patricia: Two numbers have a ratio of 5:3. The larger number is 36 more than half the difference of the two numbers. What are the two numbers? Answered by Penny Nom.
	Augmented matrix		2002-12-31
		From Michelle: I am trying to augment a matrix so that i can find the values of the variables a, b, and c. For the life of me i can't find a solution to the matrix: 3 -5 2 ' 22 2 3 -1 ' -9 4 3 3 ' 1 I thank you for your help, Michelle Answered by Penny Nom.
	Successive coefficients in Pascal's Triangle		2002-12-27
		From Quincy: There is a formula connecting any (k+1) successive coefficients in the nth row of the Pascal Triangle with a coefficient in the (n+k)th row. Find this formula Answered by Penny Nom and Walter Whiteley.
	Averages of Averages		2002-12-21
		From Amy: If in the month of October the % of Payments Received was 80.74% and in November it decreased to 69.36%. Can you take the 80.74-69.36/69.36 to get the % of difference. In otherwords can you take the % of difference when the numbers you are comparing are %'s???? Can you also take an average of an average? For example, average number of payments received in October was 25.00%, average number of payments received November was 50.00%, and the average number of payments received in December was 15.00%. Do you average (25.00%, 50.00% and 15.00%) or do you have to go back to the numbers that calculated the averages. For example, October 25.00% was based on 25 payments being received out of a possible 100. So instead of taking the average of the averages, do you take the average payments and the average customers over the 3 months and calculate the average??? Answered by Harley Weston.
	20% of 40% of 500		2002-12-19
		From Richard: What is 20% of 40% of 500? Answered by Penny Nom.
	The intersection of conics		2002-12-19
		From Glenda: We are studying systems of equations where two conic sections are the two equations that we are solving simultaneously. We were studying the number of solutions that are possible if you have an ellipse and a parabola. We all agree that there can be none, one, two, three or four solutions. The question that the students had for me was whether or not a portion of an ellipse and a parabola can overlap and thereby allow an infinite number of solutions. What should I tell them? Answered by Chris Fisher and Harley Weston.
	The units digit of 2 to the power of 31921		2002-12-18
		From A student: If 2 to the power of 31921 is multiplied out, what will be the units digit? Answered by Penny Nom.
	Odd and even		2002-12-17
		From Martin: I am a graduate engineer trying to teach single digit addition to my 8 year old grand-daughter. My questions follow. Assume a child does not know what multiplication and division are. Assume the child knows how to count from 0 to 10 How do you explain that 2, 4, 6, 8 and 10 are even numbers And 1, 3, 5, 7 and 9 are odd numbers And these three facts? when you add two even numbers, the answer is even when you add two odd numbers, the answer is even when you add an even number and an odd number, the answer is odd? Can all of these be reasoned out, without using the concepts of multiplication or division? Answered by Diane Hanson.
	Un peu de trigonométrie		2002-12-16
		From Hubert: J'ai 37 ans et les mathématiques sont relativement loin dans ma mémoire, je voudrais savoir s'il existe un méthode pour résoudre une équation du type. a1*cos(x) + a2*sin(x) + a3*cos(2x) + a4*sin(2x) + a5 = 0 Answered by Claude Tardif.
	Calculations		2002-12-15
		From Mahdi: This problem is rather general, but it usually makes a lot of problems. I almost have no difficulty in math and physics questions, but unfortunately I'm not at all accurate in simple one or two digit calculation. I even sometimes make silly mistakes in simple sums like 7+4=12 or 4+5=11! Is there any effective way to reduce these mistakes? Answered by Walter Whiteley.

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