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Proving a summation formula by induction |
2006-04-19 |
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From Sharon:
Prove by induction that the sum of all values 2^i from i=1 to n equals 2^(n+1) - 2 for n > 1.
Answered by Stephen La Rocque. |
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Equation of a line in Ax + By = C form |
2006-04-19 |
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From Christopher:
How do you write the equation of a line with a slope of 3/8 and passing through (-4,6) in Ax+By=C form?
Answered by Stephen La Rocque. |
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How much money can I borrow if I have $5 000 for a deposit? |
2006-04-19 |
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From Chris:
I have a sum of cash that I want to use as a deposit ($ 5 000) and a lender will lend me 65% of the purchase price. How do I calculate the maximum value I can borrow?
Answered by Stephen La Rocque. |
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Which has more pizza? |
2006-04-19 |
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From Kristine:
Which has more area: a round pizza that is 16 inches in diameter or three square pieces of pizza that are 8.5 inches on each side?
Answered by Stephen La Rocque. |
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Arithmetic and Geometric Sequences |
2006-04-19 |
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From Skye:
If the 1st, 4th, and 8th terms of an arithmetic sequence are consecutive terms in a geometric sequence, find the common ratio of the geometric sequence.
Answered by Stephen La Rocque. |
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How many numbers are relatively prime with 250? |
2006-04-19 |
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From David:
How many positive integers less than or equal to 250 are relatively prime with 250?
Answered by Stephen La Rocque. |
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Reverse percentage |
2006-04-19 |
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From Mike:
How would I calculate a reverse percentage?
Let me give you an example. I have two values that calculate to a success rate of 93.32. Total=1546051 Failures=103302. (1546051-103302)/1546051=93.32% success.
Now how much would I need to increase the total value to get the success up to 95%?
Answered by Stephen La Rocque. |
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How do you round off 89,100? |
2006-04-19 |
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From Jeannie:
My home work says to round each number to the place of the underlined digit. It has 89,100. The underlined number is 9. What do I do?
Answered by Stephen La Rocque. |
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Finding c in 4x=10-cy |
2006-04-19 |
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From Jennifer:
A solution of the equation 4x=10-cy is (5,2). What is the value of c?
Answered by Stephen La Rocque. |
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Cubic yards of landscape stone |
2006-04-19 |
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From Janet:
I need to spread landscape stone around my pool. A landscaper said I need 16 yards. What is the area of a cubic yard if I want the stone 3" deep?
Answered by Stephen La Rocque. |
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Three circles inside a larger circle |
2006-04-16 |
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From Meghan:
Given three congruent circles tangent to one another (radii = 1), what is the radius of a circle circumscribed around them?
Answered by Stephen La Rocque. |
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Mayan multiplication |
2006-04-16 |
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From Marca:
I'm researching the Mayans, and my advisor, Dr. McDonald, stated that you may know whether the Mayans knew how to multiply. I'm finding conflicting information on the internet, and anything you could provide would be greatly appreciated.
Answered by Chris Fisher. |
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Volume of a tennis ball can |
2006-04-16 |
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From Jon:
Tennis balls are generally packaged in circular cylinders that hold 3 balls each. The diameter of a tennis ball is 6.5 cm. Find the volume of a can of tennis balls.
Answered by Stephen La Rocque. |
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How many arrangements are there? |
2006-04-16 |
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From Jim:
Can you tell me how many different combinations there are using 3 letters and 4 numbers. Letters first then numbers, example -aaa0001, aaa0002, aaa0003,-----------baa0001, baa0002, ------zzz9999.
Answered by Stephen La Rocque. |
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Overlapping area of two circles |
2006-04-15 |
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From Jade:
Given two identical circles where the radius (6 units) is the distance between the centers, what is the area of the overlapping region?
Answered by Stephen La Rocque. |
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