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The length is twice its breadth |
2010-12-09 |
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From jenu:
The length of the rectangular field is twice its breadth. A man jogged around it 5 times and covered a distance of 3 km. what is the length of the field?
Answered by Penny Nom. |
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80 miles in 40 minutes |
2010-12-08 |
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From james:
i travel 8o miles in 40 minutes. how fast am i going in mph
Answered by Penny Nom. |
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A rectangular solid |
2010-12-08 |
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From ryan:
Good day!
Have a question on rectangular solids. We were asked to find the dimensions of a rectangular solid, we were only given the volume of the rectangular solid, the total area, and the altitude. I tried using the volume of the rectangular solid and was able to get the area of the base, but I don't know how to get its length and its width. Hope you could help me again. Thanks!
Answered by Penny Nom. |
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Sales as a function of advertising |
2010-12-08 |
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From Adori:
The sales S(in thousands if units) of a product after x hundred dollars is spent on advertising is given by S=10(1-e^kx). Find S as a function of x if 2500 units are sold when $500 is spent on advertising.
Answered by Penny Nom. |
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A water tank has the shape of a right circular cone |
2010-12-07 |
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From mike:
A water tank has the shape of a right circular cone with height 12 feet and radius 8 feet. Water is running into the tank so that the radius r (in feet) of the surface of the water is given by r=0.75t where t is the time (in minutes) that the water has been running. the volume V of the water is given by V=1/3 pi r^2h. Find V(t) and use it to determine the volume of the water when t=5 minutes.
Answered by Penny Nom. |
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A television camera at a basketball court |
2010-12-06 |
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From ryan:
Can you just please give me an idea on how the diagram would look like. I'm really confused.
A television camera is 30 ft. from the sideline of a basketball court 94 ft long. The camera is located 7 ft from the midcourt. Through what angle must it sweep in order to cover all action on the court?
Answered by Penny Nom. |
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Simultaneous equations |
2010-12-05 |
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From ryan:
Question from ryan, a student:
3 4
-- - -- = 1 (1)
x y
7 2 11
-- - -- = -- (2)
x y 12
Answered by Chris Fisher and Stephen La Rocque. |
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The percent-day method |
2010-12-04 |
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From Kenneth:
I read about this method in an old business mathematics book and was curious about how it works to produce the correct answer.
“Percent-day method is based on 360 days’ time and 1% interest. Any interest rate multiplied by any number of days is equal to so many %-days.”
Example: 82 days at 5% equals 410%-days.
Answered by Penny Nom. |
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Fifty votes were cast in a class election |
2010-12-03 |
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From nympha:
Fifty votes were cast in class election, Beth got 1/5 of the votes. Helen got as many votes as Jane and Peter put it together. Peter got 1/3 as much votes as Jane. How much votes did each of the four candidates received?
Answered by Stephen La Rocque. |
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Angular speed |
2010-12-03 |
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From Julie:
If the angular speed of a circle is 360 degrees divided by the time it took to rotate,
how do I calculate ones that have greater rotations than the amount of time?
I mean, you calculate the angular speed of a merry-go-around that spins once every 5 seconds
by doing 360degrees/5 sec, but how do you calculate a merry-go-around that has 16 rotations every 4 seconds?
Answered by Penny Nom. |
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Simplify the logarithmic expression |
2010-12-02 |
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From Adori:
Use the properties of logarithms to simplify the logarithmic expression. Log(1/250) base 5
Answered by Penny Nom. |
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Two chords in a circle |
2010-12-02 |
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From girma:
one chord of a circle is 8cm long and it's distance from the center is 4cm long.what will be the length of another chord, of the same circle ,which is 2cm from the center
Answered by Penny Nom. |
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Find all the roots |
2010-12-02 |
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From gagan:
find all the roots of z^5-3z^4+2z^3+z^2-3z+2
Answered by Stephen La Rocque and Penny Nom. |
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A normal distribution problem |
2010-12-02 |
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From Racquel:
I am stuck on this question. I am not sure if using the z score will help
me get the answer I need. Here is the question?
The average length of time per week that students at this university spend
on homework is normally distributed with a mean of 18 hours and a standard
deviation of 3 hours. If Diane spends more time on homework each week than
75% of students, what is the minimum time she must spend?
Answered by Penny Nom. |
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The height of the trapezoid |
2010-12-01 |
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From Ryan:
A trapezoid has an area of 10.5 cm squared and parallel sides that
measure 5.0 cm and 2.0 cm what is the height of the trapezoid
Answered by Penny Nom. |
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