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Seven digit numbers |
2005-06-23 |
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From Ky:
How many number combinations are possible for a 7-digit number? How many people in a population can exist without having to exceed the seven digit combinations and having to revert to a 8 or 9 digit number?
Answered by Penny Nom. |
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Profit of more than 100% of cost |
2005-06-22 |
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From sam:
I know I can work out what percentage profit I am making by : profit/cost x 100, and I can work out up to 99% profit (the way I currently calculate it is profit x 1.99) But how do I work out any amount over 100%, say for instance I have something that costs me $0.52 that I wish to sell for 250% profit?
Answered by Penny Nom. |
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An algebraic remainder |
2005-06-22 |
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From Raymond:
Given that 4x3 - kx is divisible by 2x+1, find the remainder when the expression is divided by 4 - x2.
Answered by Penny Nom. |
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A geometric sequence |
2005-06-21 |
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From A student:
The first three terms of a geometric series are 3(q+5), 3(q+3), (q+7) respectively.
Calulate the value of q.
Answered by Penny Nom. |
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Discriminant |
2005-06-20 |
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From A student:
If a quadratic has real root, its discriminant b2-4ac>=0 Is there any similar condition or method by which you can find whether roots of a cubic equation are real or not?
Answered by Chris Fisher. |
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An octagonal gazebo |
2005-06-19 |
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From Tucker:
I want to build a gazebo that is a regular octagon 15 feet across. How do I figure the length of each side?
Answered by Harley Weston. |
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An integer x when divided by 5 leaves the remainder 3. |
2005-06-18 |
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From A teacher:
An integer x when divided by 5 leaves the remainder 3. Prove that when 4x is divided by 5, 2 is the remainder
Answered by Penny Nom. |
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Two tangents to a circle |
2005-06-18 |
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From Tej:
The tangents drawn from points M and N of a circle
having centre O intersect each other at point P. If
angle MPN=60 degrees, NM=10, then find the radius of
the circle and Area of quadrilateral OMPN.
Answered by Penny Nom. |
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p+1, p+2 y p+4 are prime |
2005-06-18 |
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From Vincent:
Find all the values of p (where p is a natural number), for which the numbers p+1, p+2 y p+4 are prime.
Answered by Penny Nom. |
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combien de fruits de chaque sortes? |
2005-06-13 |
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From Halloy:
j'ai un panier de 32 fruits au total dans mon panier, j'ai 3 fois plus de bananes que de pommes et 4 fois plus de poires que de pomme. Combien il y a de bananes, de poires et de pommes dans mon panier?
Answered by Claude Tardif. |
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In how many ways can 12 different fruits be distributed |
2005-06-13 |
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From Sapta:
In how many ways can 12 different fruits be distributed among 3 boys so that each receives at least 1 fruit?
Answered by Claude Tardif. |
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20% profit |
2005-06-12 |
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From Shawn:
If I know that I will be paid, say, $150.00, for labor, and I want to make
20% profit on what I pay for the labor, what is the calculation and factoring
process?
I see it like this
(x*.2)+x = 150
but I don't know how to factor it out from there.
Answered by Penny Nom. |
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The sum of the digits of 2^100 |
2005-06-11 |
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From Richard:
The sum of the digits was calculated for the number 2100, then the sum of the digits was calculated for the resulting number and so on, until a single digit is left.
Answered by Penny Nom. |
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The size of a lot |
2005-06-09 |
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From Bob:
Is it possible to determine the square footage and acreage of a residential lot that's straight on 3 sides, and triangular on the 4th side?
As shown in the crude sketch below, the two legs of the triangle at the back end of the lot are 61' and 62'.
Answered by Penny. |
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Digging a hole for a pool |
2005-06-08 |
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From Debra:
I need to have dirt hauled away from my built in pool and the haulers are asking me how many yards of dirt there is. How would I figure that out? It is a 24 ft round pool and 3 inches of soil depth was dug out.
Answered by Penny. |
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