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One percent of a billion |
2003-09-04 |
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From Charles: What is one percent of one billion? Answered by Penny Nom. |
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Positive, negative and zero |
2003-09-04 |
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From Brian: Can the Value of zero be positive or can it be negative or can it be both. Answered by Penny Nom. |
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The game of 24 |
2003-09-03 |
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From A student: We have a game where four numbers must equal 24 using addition, subtraction, multiplication and/or division.Ý I am stuck on the following four numbers - 12, 24, 9 and 17. Answered by Penny Nom. |
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A boat travels 12 km upstream... |
2003-09-03 |
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From Sohaib: A boat travels 12 km upstream and back in 1 hour 45 minutes. If the speed of the current is 3km/hr throughout, find the speed of the boat in still water, giving your answerÝcorrect to 3 decimal places. Answered by Penny Nom. |
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Why percentage? |
2003-09-03 |
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From Vicky: My cousin aske me a question about the use of percentages and I'm not sure how to answer it. He wants to know why when there is a sale in a shop we use percentages and not fractions or decimals. Answered by Penny Nom. |
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Percentage markup |
2003-09-03 |
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From Virginia:
I am confused and hope you can help. I have looked high and low for a "chart" persay to go by when I am having to calculate markup percentages. Example if I have a List price of $1838.00 and my cost is $955.76 and I want to mark it up 30%. My colleage says it should be divided by .7 I don't understand how he arrives at .7 from 30 percent. Answered by Claude Tardif. |
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Profit margin |
2003-09-03 |
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From Chet:
My salesman calculates a customers profit margin by dividing what the customer paid by what he sells for, then subtracting that answer from 1. For example a customer sells a product for $15. He bought it for $10. 15/10=.66 Subtract that from 1 and get a profit % of 33% Here's my question: If I want to figure what a reseller will sell a product for if he wants 40% margin(by the technique above), what formula do I use? Let's say I want to sell a product for 8.50, and I want the reseller to make 40% Answered by Penny Nom. |
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Two row arrays |
2003-09-03 |
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From Madalyn: My question is, what are #'s that can not be arranged in two row arrays called? Answered by Penny Nom. |
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A helicopter rises vertically |
2003-09-02 |
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From Kate: A helicopter rises vertically and t seconds after leaving hte ground its velocity is given in feet per second by v(t) = 8t + 40 / (t+2)2 How far above the ground will the helicopter be after 3 seconds? Answered by Penny Nom. |
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Water in a tank |
2003-09-02 |
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From A parent: if a tank is 48 inches long 14 inches wide and 18 inches deep if a yardstick was inserted into the tank and measured 2 inches of water in the tank how many gallons of water would be in the tank. Answered by Penny Nom. |
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A theorem in geometry |
2003-09-02 |
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From Diego: Please refer to figure in attached file. P is a point on the chord AB of a circle such that the tangent PT which touches the circle at T is equal to AB. How do we prove that PT2 = AP x BP. Answered by Dieter Ruoff and Penny Nom. |
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The units digit of 57 to the 28th power |
2003-09-01 |
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From Maria:
If 57 is raised to the 28th power, what must be the units digit in the result? If you raise 7 to the 500th power, what is the numeral that will appear in the units digit position? Answered by Penny Nom. |
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A 6 team schedule |
2003-08-31 |
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From A scheduler: I saw that someone put on your web site a team schedule and you helped them figure it out.Ý I have 6 teams that want to play each other once, and believe it or not, I cannot figure it out. Answered by Penny Nom. |
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20% of 40% of 500 |
2003-08-31 |
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From A student: What is 20% of 40% of 500? Answered by Penny Nom. |
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Terminology |
2003-08-31 |
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From Maria: My daughter Veronica is a rising 6th grader and has to complete some Summer Math assignments and would like to ask you three questions: - ___________ are number pairs that have a product of 1.
- You can name any point on a plane with two numbers. These two numbers are called _____________.
- A _______________ is the size of a cube that is exactly 1 inch on each edge.
Thanks, Answered by Penny Nom. |
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