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A normal distribution problem |
2005-08-08 |
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From Brad:
The life of a toy is normally distributed. Suppose 92.51% of the items lives exceeding 2,160 hours and 3.92% have lives exceeding 17,040 hours. Find the mean and the standard deviation.
Answered by Penny Nom. |
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Area of a lot |
2005-08-07 |
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From John:
We hope this copy of our survey map will help you to determine the acreage of our land.
Answered by Harley Weston. |
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Converting rational numbers |
2005-08-07 |
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From Joe:
I am helping my son with his converting rational
numbers in the form of A/B where A and B are integers and
B not equal to zero
I think I am doing this right but I am not sure so
below are the problems and our answers are beside
them, please let me know if these answerers are correct
Answered by Penny Nom. |
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A golf outing for 16 golfers |
2005-08-05 |
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From Bob:
I have a golf outing fast approaching and I’m having a problem matching the golfers so that everyone plays a round of golf with every other golfer in the group.
My problem is this: I have 16 golfers playing 5 rounds of golf. I would like a different foursome for every round of golf, that is each round (5 total) an individual is playing with 3 other players he hasn’t played with as of yet. Can you crunch the numbers and get back to me?
The way I see it, we have 20 combinations (5 rounds x 4 golfers) with numbers 1 thru 16.
Answered by Chris Fisher. |
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What is the radius of this planet |
2005-08-05 |
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From Kelly:
Assuming that a North-South line has been established, you set up two camps that are 67 miles apart. You now set up poles at each camp perpendicular to the ground. On a certain day at "noon" the pole at the South camp casts no shadow, while at the North camp a shadow is cast. The shadow makes an angle of 89 degrees with the horizontal. What is the radius, diameter, and circumference of this planet?
Answered by Chris Fisher. |
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Cubic yards of sand |
2005-08-04 |
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From Beth:
I am trying to figure out how much sand I will need for ground cover under my children's playset. The area to cover is 30' x 30' and I want 4 inches of sand.
Answered by Penny Nom. |
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0.02 acres |
2005-07-31 |
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From Negin:
know how much is 0.02 acres in square footage?
Answered by Penny Nom. |
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A perfect square that is equal to 1 acre |
2005-07-31 |
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From Shannon:
If you have a perfect square that is equal to 1 acre, what is the length of the sides and how do you do it?
Answered by Penny Nom. |
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A television antenna sits on a roof. |
2005-07-30 |
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From Liz:
A television antenna sits on a roof. Two 76-foot guy wires are positioned on opposite sides of the antenna. The angle of elevation each makes with the ground is 24 degrees. How far apart are the ends of the two guys wires?
Answered by Penny Nom. |
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A concrete slab |
2005-07-29 |
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From Armand:
I am
planning to pour a concrete slab over an existing slab in my garage
which is very uneven, with a depth variation from 2 1/2 inches to 5 1/2
inches from level. I'm afraid to over estimate concrete since it will be
wasted but worse, I'm afraid to underestimate. I've broken the slab down
into four sections with the following being the four dimensions, can you
tell me how much concrete I will need please, I would very much
appreciate your help.
1- 6ft/8in x 20ft x 4 1/2 in. thick
2- 16ft/10in. x 20ft x 3 1/2 in. thick
3- 6ft/6in. x 16in. x 5 1/2 in. thick
4- 6ft/6in. x 8ft. x 4in. thick
Answered by Penny Nom. |
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Speed on a bicycle |
2005-07-27 |
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From Deborah:
We are trying to figure out how many miles per hour we rode in a bike race. If the distance was l5 miles and the time it took was was 55 minutes, what is the speed?
Answered by Penny Nom. |
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Cubic feet in a mobile home |
2005-07-22 |
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From Jeanne:
my mobile home is 24 x 56. I'm trying to find out how many cubic feet this is. I'm going to set of some bug bombs and it says 1 can will cover 4000 cubic feet. I don't know how to figure my cubic feet. the ceilings are 8 ft high everywhere but the living and dining room. They are vaulted and approximately 10 feet at the peak. I just need an estimate.
Answered by Penny Nom. |
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Some geometry problems |
2005-07-22 |
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From Sherry:
1. If Circle K has tangents RT and TY where R and Y are the points of tangency, then angle RKY and angle RTY are supplementary.
2. If one diagonal bisects a pair of opposite angles in a quadrilateral, then the quadrilateral is a kite.
Answered by Penny Nom. |
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A set of numbers whose sum is 1 |
2005-07-21 |
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From Santos:
Does there exist a set of numbers whose sum is 1, and the sum of whose squares is less than 0,01?
Answered by Paul Betts. |
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The period of sin(x) + cos(x) |
2005-07-21 |
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From A student:
WHAT IS THE PERIOD OF SIN(X)+COS(X)?
Answered by Penny Nom. |
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