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A worm crawling home |
2004-02-18 |
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From Cindy: A worm is crawling to his home which is one meter away. The longer he crawls the weaker he gets and the less he can crawl the next day. If he crawls within 1/3000 of a meter of his home, he will find food. He must eat within twelve days. The first day he crawls 1/2 meter. The second day he crawls 1/4 meter. The third day he crawls 1/8 of meter. This pattern continues for twelve days. Make a Chart that shows the distance he has covered at the end of each day and the total he has covered at the end of each day. Does he make it to the Food in time? Answered by Penny Nom. |
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Nonconvex shapes |
2004-02-18 |
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From Merrill: Draw 4, 6 and 8 sided shapes so that ONE straight line can be drawn through each side Answered by Chris Fisher and Penny Nom. |
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Acres and square miles |
2004-02-17 |
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From Richard:
How many acres are in .17 square miles? and How many acres are in .6 square miles?
The two areas I am requesting information about are Vatican City and San Marino, the two smallest countries in the world. If I can transfer the sq. miles into acres , I can relate the size of these countries to our school grounds and the students will better understand their sizes.
Answered by Penny Nom. |
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Grams and Milliliters |
2004-02-17 |
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From Chantal: We have to do a "thing", and I need to convert grams into mililitres (g into mL). how can I do this? Answered by Penny Nom. |
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Areas, perimeters and derivatives |
2004-02-15 |
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From Geoff: A recent lecture in my calculus class led me to realize that the derivative of the area of a circle, with respect to the radius is equal to the circumfrence. This also holds true for the relationship between the volume of a sphere and the surface area of that sphere:
why do these hold true? why is it only for circular objects? Answered by Harley Weston. |
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An arc on a train track |
2004-02-15 |
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From A student: I'm trying to build a route in a train simulator program. I have a curve to the right (an arc, in other words) with a length of 25 meters and the radius is 1,500 meters. Let's say point P is the beginning of the curve (arc) and point Q is the end point of the arc. Then picture a tangent to point P. I need to find the length of a line perpendicular to that tangent that runs to point Q (the end of the curve/arc). Answered by Penny Nom. |
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The derivative of x to the x |
2004-02-14 |
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From Cher: what about the derivative of x to the power x? Answered by Penny Nom. |
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The substitution method |
2004-02-14 |
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From Keisha: I need to solve this problem by using the substitution method.
3x+y=1
x=2y+5
Please help me understand the method to solve. Answered by Penny Nom. |
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Probabilities and olivies |
2004-02-14 |
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From Annetta: A bowl contains five green olives and eight black ones. Wilma sticks a fork into a bowl and brings out two olives. What is the probability that she gets one green and one black olive? Answered by Harley Weston. |
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Red riding hood |
2004-02-14 |
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From Frank: Red riding hood had a number of jars to take to grandma's house. As she traveled she gave away 1/3 of them to an old lady. Then later As she walked through the forest a wolf stole 1/2 of her remaining jars. When she arrived at grandma's house she gave her 2/3 of the remaining jars. She kept 6 jars for herself. How many jars did she start out with. Answered by Diane Hanson. |
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A pyramid-shaped tank |
2004-02-13 |
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From Annette: The base of a pyramid-shaped tank is a square with sides of length 9 feet, and the vertex of the pyramid is 12 feet above the base. The tank is filled to a depth of 4 feet, and water is flowing into the tank at a rate of 3 cubic feet per second. Find the rate of change of the depth of water in the tank. (Hint: the volume of a pyramid is V = 1/3 B h , where B is the base area and h is the height of the pyramid.) Answered by Harley Weston. |
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Fractions |
2004-02-13 |
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From A parent: 12/36=?/18=4/?=?/9 Answered by Penny Nom. |
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Common fractions to decimals |
2004-02-12 |
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From A parent: I'm trying to help my son work with turning fractions into decimals and this seems foreigh to me after 20 years of not being in school. Can you give me a few illustrations and/or examples of how to do that?? Answered by Penny Nom. |
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Profit |
2004-02-12 |
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From Mohamed: if i bought some thing with 100$ and the saller told me that his profit was 30% how can i know the actual price of the good Answered by Penny Nom. |
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Zero |
2004-02-12 |
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From Syazwan: can you tell me who and when the number zero was
discoveredd Answered by Penny Nom. |
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