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Expand and Simplify (3x+5)(5x-9) |
2015-04-23 |
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From chloe:
Expand and Simplify (3x+5)(5x-9)
Answered by Penny Nom. |
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Two concentric circles |
2015-04-21 |
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From Juniper:
Two concentric circles have radii of 4 cm and 8 cm. A segment is drawn so that it is tangent to the smaller circle and a chord of the larger circle. How long is the segment?
Answered by Penny Nom. |
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A circle inscribed in a square |
2015-04-19 |
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From michael:
A circle is drawn in a square PQRS. If the total area of the shaded portion of the square is 42 cm square, calculate the radius of the circle
Answered by Penny Nom. |
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A geometric sequence |
2015-04-19 |
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From Delfina:
In a geometric sequence the second term is 15 and the fifth term is -405. Find the sum of the first eight terms
Answered by Penny Nom. |
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An inequality |
2015-04-19 |
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From mr.:
Simplify the inequality √x>x and represent on a number line
Answered by Penny Nom. |
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A wireless fence |
2015-04-18 |
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From Dave:
I'm buying a wireless fence to keep my pet in my yard. It has a half acre range. In a straight line how far would that be?
Answered by Penny Nom. |
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Two cars approaching an intersection |
2015-04-16 |
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From Engabu:
Car A is traveling west at 50km/h & car B is traveling north at 60km/h. both are headed for the intersection of the two roads. At what rate are the cars approaching each other when car A is 3km & car B is 4km from the intersection?
Answered by Penny Nom. |
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How many boats total are in the marina? |
2015-04-15 |
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From Carla:
In a marina, 3/4 of the boats are white, of the remainder 4/7 are blue, the rest are red. There are 9 red boats. How many boats total are in the marina? My answer is 84 because if 1/4 of the boats are divided into sevenths, that makes the whole marina a 28 part item. 3/28 are red so 84 is the total number of boats. My child thinks I am wrong.
Answered by Penny Nom. |
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Two airplanes |
2015-04-14 |
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From john:
two planes leave an airport at the same time, one going northwest (N35*W)at 400 mph and the other going east at 332 mph. How far apart are the planes after 4 hours to the nearest mile?
Answered by Penny Nom. |
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Constructing a box of maximum volume |
2015-04-14 |
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From Margot:
I need to do a PA for maths and I'm a bit stuck.
The PA is about folding a box with a volume that is as big as possible. The first few questions where really easy but then this one came up.
8. Prove by differentiating that the formula at 7 does indeed give you the maximum volume for each value of z.
Answered by Penny Nom. |
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Team selection |
2015-04-13 |
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From Peter:
I manage a football team with a list of 28 players.
Only 24 can play each game.
The season is 16 games.
How do I fairly select 24 players each week.
Answered by Robert Dawson. |
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Some non-decreasing sequences |
2015-04-13 |
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From Sky:
Hi I'm a Student and i'll try my best to state the problem perfectly.
The number of non-decreasing sequences of size at least 1 and at most N,
such that each element of the sequence lies between L and R, both inclusive.
Eg:- N=1 L=4 R=5
ans= 2. [{4},{5}]
N=3 L=4 R=6
ans= 19. [{4},{5},{6},{4,4},{4,5},{4,6},{5,5},{5,6},{6,6}
{4,4,4},{4,4,5},{4,4,6},{4,5,5},{4,5,6},{4,6,6},{5,5,5},{5,5,6},{5,6,6}
,{6,6,6}]
Answered by Claude Tardif. |
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The area of a circle given the circumference |
2015-04-12 |
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From F:
How do you find the area of a circumference of 6?
Thanks.
Answered by Penny Nom. |
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Excavating a basement |
2015-04-12 |
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From Randy:
The cost of excavation is $4.50/ cu yd. Find the cost of excavating a basement 87 ft long, 42 ft wide, and 8 ft deep.
Answered by Penny Nom. |
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Sharing $600 in the ratio of 2 to 3 |
2015-04-11 |
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From Kenneth:
Hello:
If two people share $600.00 in a ratio of 2 to 3, which calculations are correct: 2/3 X $600.00 & 1/3 X $600.00 or 2/5 X $600.00 & 3/5 X $600.00?
The denominator 5 is determined by adding 2 and 3 from the ratio.
I thank you for your reply.
Answered by Penny Nom. |
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