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What is the cost price? |
2006-04-14 |
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From Purushotham:
If the selling price is 120 and the profit is 20%, what is the cost price?
Answered by Stephen La Rocque. |
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Compound Interest Formula and explanation |
2006-04-14 |
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From Michelle:
Currently there is $10,000 in a customer's savings account that earns 4% interest compounded annually.
How much interest will the customer earn in a year?
Answered by Stephen La Rocque. |
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The product of successive terms in sequences |
2006-04-13 |
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From Forrest:
1) Find three successive terms in an arithmetic sequence such that their sum is 24 and their product is 440
2) Find three successive terms in a geometric sequence such that their sum is 21 and their product is 216
Answered by Penny Nom. |
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Price percentages |
2006-04-13 |
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From Kristine:
An item that is no longer on sale at "25% off" receives a price tag that is 33 1/3% more than the sale price. Has the item price been restored to its original price? Why or Why not?
Answered by Stephen La Rocque. |
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Perimeter of a triangle atop a square |
2006-04-13 |
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From Mary:
There is an (irregular) pentagon that is made up of a square and a triangle. The triangle is directly on top of the square. The triangle is a right triangle. One of the angles is 45 degrees. One of the sides of the triangle is 4. What is the perimeter of the pentagon?
Answered by Penny Nom. |
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Cone dimensions |
2006-04-12 |
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From Mirnela:
The height of a cone is 40 and the radius is 9. How
do I find the slant height of this?
Also, how do I find the area of the base of a cone if the radius is 7?
Answered by Stephen La Rocque. |
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How to find the odds for a lottery jackpot |
2006-04-12 |
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From Harvey:
Is it best to use factorials to calculate the odds of winning a lottery, such as the MegaMillions that is popular in the US, or is there a better way?
Answered by Stephen La Rocque. |
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Finding the inverse of a function |
2006-04-12 |
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From Sam:
If g(x) = 2x+3/5 then how do I find the inverse?
Answered by Walter Whiteley. |
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Probability of a committee with 3 parents and 3 teachers |
2006-04-12 |
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From Javier:
A committee consisting of 6 people is to be selected from 8 parents and 4 teachers. Find the probability of selecting 3 parents and 3 teachers.
Answered by Stephen La Rocque. |
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Finding square roots |
2006-04-12 |
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From Fehmida:
I would like to know about tricks or formulas to do complicated square roots.
ex. square root of 1029
Answered by Penny Nom and Steve La Rocque. |
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Arithmetic Sums |
2006-04-12 |
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From Angel:
(a) In a particular arithmetic sequence, u6 = 344.5 and u20 = 88.3. Find S28.
(b) In a particular arithmetic series, S10 = 495 and S15 = 1005. Express S15 in sigma notation.
Answered by Stephen La Rocque. |
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The average of a function |
2006-04-11 |
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From Justin:
Find the average value of the following function from x=0 to x=7
f(x)=3x+4
Answered by Penny Nom. |
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Sum of a Geometric Sequence |
2006-04-11 |
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From Andre:
In a particular geometric sequence, U3=-3.6 and U10=12.9. Find S16 and S17.
Answered by Stephen La Rocque. |
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The area of a regular hexagon |
2006-04-10 |
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From A student:
find the area of a regular hexagon with a apothem of 9
Answered by Stephen La Rocque. |
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An epicycloid |
2006-04-10 |
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From Sharon:
What is the name of the curve formed by a point on the circumference of a circle that rolls on the outside of a fixed circle? This curve is used in the study of gears.
Answered by Stephen La Rocque and Penny Nom. |
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