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A pile of soil that is 284' around and 12' high |
2007-07-26 |
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From bev:
I have a pile of soil that is 284' around and 12' high. I need to know how many yards are in that pile. And then how do I convert that to cubic yards
Answered by Penny Nom. |
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Multiplcation of two negative numbers |
2007-07-26 |
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From Brett:
Someone asked a question about multiplication and division of two negative numbers yielding a positive result here:
http://mathcentral.uregina.ca/qq/database/QQ.09.99/butler1.html I was not fully happy with the explanation b/c I want to give me daughter a real-world example and I can't seem to find one.
The following illustrates why multiplying negative numbers has become difficult to explain:
2 X 2 = 4
----(-4)---(-2)---0---2---4
In this example we start with 2 and then want 2 more of them.
When we move across the number line from 2 to our answer, which is four, we have moved only 2 units to the right.
-2 X -2 = 4
----(-4)---(-2)---0---2---4
In this example we start with -2 and then want -2 more of them.
When we move across the number line from -2 to our answer, which is four, we have moved 6 units to the right.
How can the phenomenon of multiplying two negative numbers being more powerful than multiplying two positive numbers be explained?
-Brett
Answered by Stephen La Rocque and Harley Weston. |
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A cone with two fruits |
2007-07-26 |
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From Meg:
You have a cone shaped bag. At the bottom of the bag is an orange with
radius r. On top of the orange is a melon with radius R. It touches the
orange and fits snugly in the bag, touching it in a ring around the orange.
Its top is at the same level as the top of the bag. What is the radius of the
cone?
Answered by Stephen La Rocque. |
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Cubic metres of topsoil |
2007-07-25 |
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From Laurie:
How do I convert cubic meters to square meters?
Answered by Harley Weston. |
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Simplifying an algebraic fraction expression |
2007-07-25 |
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From Jessica:
How do I simplify b/(b2-25) + 5/(b+5) - 6/b?
Answered by Stephen La Rocque. |
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Guessing multiple choice answers |
2007-07-24 |
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From carla:
You are taking a multiple choice quiz that consist in 3 questions, each question has
3 possible answers only one is correct. To complete the quiz you randomly guess the answer
to each question . Find the probability of guessing exactly 2 answer correctly. b) at least to answer correctly . c)less than two answer correctly
Answered by Stephen La Rocque. |
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Countable and uncountable sets |
2007-07-24 |
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From Mac:
Hi, i tried to read few webpages related to the countably infinite and uncountable sets.
Even i read few questions from this forum.
But i am not convinced with this explanation. If you have any good book that
explains this in layman term, please redirect me to that.
1) Can you please explain what is the difference between these too ?
2) How could you say set of Natural number and set of even numbers are countably
infinite ?
N={1,2,3,...} and Even= {2,4,6,...}
When an element in the even set is some 2n, we will map it to 'n'.So
now we have a bigger number(2n) right ?
Sorry, i didn't understand that.
...
Can you please help me out to understand that ?
Answered by Harley Weston. |
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Area of a star in a regular pentagon with side length 10cm |
2007-07-24 |
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From Chetna:
A regular pentagon with side 10 cm has a star drawn within (the vertices match).
What is the area of the star?
Answered by Stephen La Rocque. |
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(1 - i)^5 |
2007-07-24 |
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From sofia:
Compute the given arithmetic expression and give the answer in the form a + bi where a,b element in R.
1. (1 - i)^5
Answered by Harley Weston. |
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A one to one function |
2007-07-24 |
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From Marsia:
Explain what it means for a function to be one to one.
Answered by Harley Weston. |
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A complex number in polar form |
2007-07-23 |
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From roland:
write the given complex number z in polar form lzl(p+qi) where lp + qil=1 for 3 - 4i.
Answered by Harley Weston. |
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Angle of depression |
2007-07-23 |
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From joyce:
hello,
here is my problem......
As you stand on a bridge w/c is 100 ft. above the water
you are looking @ an approaching barge.
If the A of top of the front of the bridge is 29.04 degrees
and the angle of depression of the rear is 17.36 degrees .
Find the length of the barge?
Answered by Harley Weston. |
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8(y + 3) + 9(y + 2) = y - 3 |
2007-07-23 |
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From jordan:
8(y+3)+9(y+2)=y-3
Answered by Penny Nom. |
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Equality of sets |
2007-07-23 |
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From Mac:
Hi, I learnt set theory recently. My teacher and few of the weblink actually give different
definition for basic set. Can you please solve this ?
My teacher says, {1,2,3} and {1,1,2,3} is also set.
But in this link http://library.thinkquest.org/C0126820/setsubset.html it says,
"A set has no duplicate elements. An element is either a member of a set or not. It cannot be in the set twice."
and "{1, 2, 3} is the same as the set {1, 3, 2, 3, 1}"
My question is,
1. Whether duplicates allowed in the set or not ?
2. Even if the duplicates are allowed, {1,2,3} and {1,1,2,2,3,3} are same or not ?
Answered by Penny Nom and Harley Weston. |
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What are the dimensions of the field? |
2007-07-23 |
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From Debourah:
a soccer field is 1080 square meters the width is 2 meters less than one-third the length. What are the dimensions of the field?
Answered by Penny Nom. |
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