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Unit conversions |
1999-04-20 |
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From Deanna:
My question has to do with unit conversions with English and metric systems. I need to know how to use conversion factors with powers of 10. Which way do i move my decimal point. ex. .48kl to liters. Thank you.
Answered by Jack LeSage. |
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A Series |
1999-04-20 |
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From Deepak Shrestha:
Given the sequence an=e^(-n*Ln(n)), does the series converge and why?
Answered by Harley Weston. |
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The halfway mark |
1999-04-20 |
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From Sherry & Tom McGee:
How do you figure the halfway mark between 1/3 and 2/3 as a fraction and a decimal point?
Answered by Penny Nom. |
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The birthday problem |
1999-04-19 |
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From Gordon Cooke:
How do I explain the rapid rise in the probability that at least two people in a group of n have the same birthday. We have derived the formula for p(n) and have graphed it and have seen how the results are counter-intuitive. At around n=23 p(n)=.5 and at n=50 p(n) is very close to 1. It does not help to simplify the problem (eg use months instead of days) because then our intuition does correspond more closely to reality. Is there some way we can see how the probabiltiy of a "collision" increases with n? It makes me think of data storage problems and hash tables in computer science.
Answered by Harley Weston. |
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Work jobs |
1999-04-19 |
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From Cindy Miller:
Hi. I'm a college student, majoring in Elementary Education. This semester I am taking a math class for elementary school teachers. I'm not sure if you can help out, but here is what I need. For the class, I am supposed to make 10 work jobs for students. Simple things that teach math that students can work on individually, for example after finishing a test. If you have any suggestions, I would really appreciate it.
Answered by Penny Nom. |
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Volume of oil in a tank |
1999-04-17 |
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From Lars Waldemarsson:
My problem is to get an equation for the depth of the oil in a gastank formed like a cylinder. The cylinder is in a horizontal position and by a stick you will be able to get the depth of the oil in the tank. All I need is an exmaple which I can build on. By this equation you will be able to get the volume of the oil if you know the depth.
Answered by Harley Weston. |
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Ounces and milliliters |
1999-04-17 |
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From Tony Rizzi:
I'm mixing a formula of: 48 oz distilled water.
15 grams of Hydroxy Ethyl Cellulose GR (powder)
30 grams of Hydroxy Ethyl Cellulose MR (powder)
200 grams of Barium Sulfate (powder)
1000 grams of Calcium Hydroxide (powder) After mixing, I need to estimate the amount of each ingredient that fits in a 3ml syringe. And how many syringes I can fill?
Answered by Harley weston. |
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y=mx+b |
1999-04-15 |
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From Selena Royle:
When solving a problem on slopes,and in the formula y=mx+b what do the M and B stand for? Why M and B?
Answered by Penny Nom. |
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Extra point questions |
1999-04-15 |
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From W Troy Council:
My teacher has given me 5 extra point questions. I have figured out two, but i need a little assistance with 3 others, could you help me with: - A stablehand agreed to work for 1 year. At the end of that time, she was to receive $240 and one horse. After 7 months she quit the job, but still received the horse and $100. What was the value of the horse?
- If the roots of x2 + bx + c are pi and square root 2, then find "b" and "c."
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Answered by Penny Nom. |
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The Binomial Theorem for rational exponents |
1999-04-15 |
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From Angela Evans:
The full question is this: Isaac Newton generalized the Binomial Theorem to rational exponents. That is, he derived series of expansions for such expressions as (x+y)-3 (x+y)2/3 (x+y)5/6 What did Newton find? What are the first four terms of the series expansions of binomials above? How can this extended Binomial Thrm. be used to aid in calculations?
Answered by Penny Nom. |
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Two contest problems |
1999-04-14 |
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From Bruce Baldwin:
We have students that are preparing for the Pythagoras Contest which is a nation wide Grade 6 math challenge. In the preparatory tests we have run into several questions that we can not understand. Is there anyone who can help us? - If 1 * 9 = 0, 9 * 8 = 72, 2 * 8 = 9, then 9 * 9 = ?
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Answered by Judi McDonald and Walter Whiteley. |
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Dividing a Circle |
1999-04-12 |
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From Mike Kenedy:
I am having trouble with a homework question for bonus marks. A Circle is continually divided by lines that do not intersect the center so that they produce the most pieces of circle. For example - 1 line divides the circle into 2.
- 2 into 4.
- 3, however into 7.
- 4 into11
- 5 into 16
- 6 into 22
- 7 into 29
- 8 into 37
- etc...
I am stumped and cannot figure out the equation, though I'm sure it involves squares. Can you help?
Answered by Penny Nom. |
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Cross-sectional area of a cylinder |
1999-04-12 |
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From Rebecca Connor:
What is the formula to find the cross-sectional area of a cylinder?
Answered by Chris Fisher. |
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Linear programming and optimization |
1999-04-09 |
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From Shams:
What is Linear programming and optimization?
Answered by Jack LeSage and Penny Nom. |
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Grade 10 math |
1999-04-08 |
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From Ron:
the type of question i'm having trouble with is 5(2x-1)=3(x-4)
Answered by Penny Nom. |
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