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Is zero a number or a place holder? |
2007-04-09 |
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From Chris:
Is zero a number or a place holder?
Answered by Penny Nom. |
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No solution to a linear system |
2007-04-09 |
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From Ryan:
When is it possible to get no solution when solving a linear system?
Answered by Leeanne Boehm, Steve La Rocque, Penny Nom and Melanie Tyrer. |
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Water is being pumped into a trough |
2007-04-09 |
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From Michael:
Water is being pumped into a trough that is 4.5m long and has a cross section in the shape of an equilateral triangle 1.5m on a side. If the rate of inflow is 2 cubic meters per minute how fast is the water level rising when the water is 0.5m deep?
Answered by Stephen La Rocque. |
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A hypothesis test |
2007-04-09 |
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From Katrina:
I have already tried to do this problem but im having a very had time with
it. Can you please help me.
Glamour Magazine sponsored a survey of 2500 prospective brides and
found that 60% of them spent less than $750 on their wedding gown.
Use a 0.01 significance level to test the claim that less than 62% of brides
spend less than $750 on their wedding gown. How are the results
affected if it is learned that the responses were obtained from magazine
readers who decided to respond to the survey through an Internet Web
site?
Answered by Penny Nom. |
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Yards of sand in a ton |
2007-04-09 |
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From Teresa:
how many yards of sand are in a ton and how many yards of limestone does it take to make a ton
Answered by Penny Nom. |
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Word problems |
2007-04-09 |
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From Danielle:
I am teaching a student who cannot understand which operation to use when doing word problems. I have tried a number of different ways to show him...any suggestions?
Answered by Haley Ess. |
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A cabinet with an arched front |
2007-04-09 |
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From Joe:
I am building an arched front cabinet that is 71 inches wide, 12 inches deep at both ends
and 16 inches deep at the center. To accurately build this cabinet I need to known the radius of
the circle that would form that arch.
Thanks,
Joe
Answered by Penny Nom. |
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Logarithms |
2007-04-09 |
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From Emi:
Given log10 2=0.30 and log10 3=0.47
How to i express 6 x 10power 14 in logarithm answer.
Please help me.
Thank you.
Emi
Answered by Stephen La Rocque. |
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Surface area of a sphere |
2007-04-08 |
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From maria:
I've read your solution to the problem of how to derive the formula of the surface area of the sphere.
But i've got a question that initially you demenstrate the area is apprximately equal to that of the lateral area of the cylinder.
Afterwards you simply say that the two areas are exactly equal. I'm very confused, how you connect your two statements together.
Can you explain to me how they are exactly equal? Your quick reply would be appreciated. Thanks for your help!
Answered by Stephen La Rocque. |
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Area of circles within a circle |
2007-04-08 |
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From Avaline:
Imagine that there are four small circles inscribed in a bigger circle. The 4 small circles are shaded. What is the ratio of the area of the shaded region to the area of the unshaded region?
Answered by Stephen La Rocque. |
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A volume of revolution |
2007-04-08 |
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From christina:
find the volume of the solid formed when region bounded by y=x/3, y=2
and the y-axis. it is revolved about the x-axis.
the assignment was to use both the washer method and the shell method
but when i solved for the volume, i got different answers.
i think my shell method is wrong because i know i'm having difficulties
with using "dy" instead of "dx"
here's my work so far:
Answered by Penny Nom. |
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An arched opening for a large doorway |
2007-04-08 |
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From Richard:
I am trying to build an arched opening for a large doorway...I know the vertical sides of the opening to be 8'-9" from the floor to the lowest point of the arch on each side...I know it is 15 1/2" from the center horizontal point to the top of the arc...I know the vertical sides are 11'-11" apart...what I need to know is the radius to create the proper arc. Can you help?
Answered by Stephen La Rocque. |
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Find the volume of the solid |
2007-04-07 |
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From tricia:
a solid is constructed so that it has a circular base of radius r centimeters
and every plane section perpendicular to a certain diameter of the base is
a square, with a side of the square being a chord of the circle.
find the volume of the solid
at first i thought the length of a side of the square would be r, but that
isn't awlays be true- only when the chord is in the center.
so how can i solve this without any values? i dont understand the relationship
between the chord and radius, except that the radius intercepts
the chord at the midpoint.
i know i hav to take the integral to get the volume,
but how do i even find the area of one of the squares?
please help,
thanks,
tricia
Answered by Penny Nom. |
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How far apart are the cars? |
2007-04-07 |
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From ian:
2 cars set off in opposite directions and travel for 6 miles,
they both take a left turn, and travel for a further 8 miles...........
how far apart are the cars???
a) 10 miles
b) 22 miles
c) 20 miles
d) 18 miles
Answered by Penny Nom. |
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How long would it take to have $100,000? |
2007-04-07 |
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From Carolyn:
If I invested $1000.00 (one time ) at 1% compounded daily, how long
would it take to have $100,000. ?
Answered by Stephen La Rocque. |
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