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Probability and a three digit number |
2001-03-15 |
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Glenn pose la question : A THREE DIGIT NUMBER IS SELECTED AT RANDOM. WHAT IS THE PROBABILITY THAT NON OF THE THREE DIGITS ARE PRIME. Harley Weston lui répond. |
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Names of the polygons |
2001-03-15 |
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Sami pose la question : I was asked to find out what the names for different polygons were. The only two I cannot find are the names for a polygon with 30 sides and a polygon with 40 sides. I would really appreciate it if you could help me. Thank you very much. Harley Weston lui répond. |
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The bond angles of a tetrahedral polygon |
2001-03-14 |
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Nishi pose la question : how do i prove (a simply as possible) why the bond angles of a tetrahedral polygon are 109.5 degrees? *i already have two explanations that i don't understand. one is about "theory of dot products" and "vectors" and a hook-like symbol w/ a cosine, and the other has an incomprhensible diagram w/ difficult notation- PLEASE BE SIMPLE! thanks sooo much Harley Weston lui répond. |
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A jogger |
2001-03-12 |
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Bill pose la question : At time t=0 a jogger is running at a velocity of 300 meters per minute. The jogger is slowing down with a negative acceleration that is directly propotional to time t. This brings the jogger to a stop in 10 minutes. a) write an expression for the velocity of the jogger at time t. b) what is the total distance traveled by the jogger in that 10-minute interval. Harley Weston lui répond. |
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Quadratic equations |
2001-03-11 |
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Philip pose la question : I am a student in the UK and i am in secondary school and i am doing my GCSE next year. here are my questions: solve the following equations correct to 2 decimal each time. [1] 2xsquared + 5x = 1 [2] 3xsquared(2x+1)=1 [3] xsquared + 7x + 2 = 2x + 4 [4] 5xsquared - 3x = xsquared + 4 Penny Nom lui répond. |
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Math Puzzle |
2001-03-10 |
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Vanessa pose la question : I have a math puzzle. I have been working on it for over 2 weeks. Here it is: use the numbers 1-25 each only once. The rows across are an equation and the columns down are an equation. There are 25 boxes. You have to use the order of operation x and / first then = and -. Some of the answers are -numbers. . . . Claude Tardif lui répond. |
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Two locus problems |
2001-03-08 |
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Janna pose la question : A point P moves such that it is always equidistant from the point G(2,5) and the line defined by y=3. Find the equation of the locus. I got as far as the equation: 3y2 -4y = -x2 + 4x - 16 and didn't know what to do from there. Of, course that whole equation could be wrong. Question 2: P is always twice as far from A(8,0) as it is from B(2,0). Find the equation of the locus. Once again, I got as far as y2 = -x2 -8x -56, and got stuck. Harley Weston lui répond. |
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The angle of elevation |
2001-03-08 |
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Jeffrey pose la question : At a Certain time, a vertical pole 3m tall cast a 4m shadow. What is the angle of elevation of the sun? Harley Weston lui répond. |
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4160 |
2001-03-07 |
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Jessica pose la question : The product of two consecutive page numbers in this book is 4160. What are the page numbers? Penny Nom lui répond. |
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problem of the week |
2001-03-06 |
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Peggy Allan pose la question : My son has been challenged with "the problem of the week" and I am unable to assist him in finding a reasonable solution. Problem 1, Julio needs to draw a line segment 15cm long. He does not have a ruler. He does have some sheets of letter size paper 28 X 21.5 cm. Describe how Julio can use the paper to measur 15 cm. Claude Tardif lui répond. |
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The substitution method |
2001-03-05 |
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A student pose la question : Solve each system of equations by the substitution method. Show your work. - y = 8
7x = 1 - y
- y = x - 1
4x - y = 19 Penny Nom lui répond. |
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Powers |
2001-03-04 |
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A student pose la question : Hey, can you show me how you do .. (2xy)to the 3rd power (x) to the 2nd power? Penny Nom lui répond. |
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Coins and monomials |
2001-03-04 |
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A student pose la question : Tokola has 5 coins with a total value of $1.05. He canot make change for a dollar, 5 cents, 10 cents, 25 cent, or 50 cents. What 5 coins does he have? and Determine whether 6c-d is a monmial. Explain why or why not. Penny Nom lui répond. |
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Arc of a sphere |
2001-03-04 |
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Some students pose la question : My friends and i have a geometry project and we cannot seem to figure out how to find the arc of a sphere. Harley Weston lui répond. |
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What is the value of n? |
2001-03-03 |
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Adam pose la question : When I add n to 7 and then divide my answer by 4,I get 5. What is the value of n? Penny Nom lui répond. |
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