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A pile of soil that is 284' around and 12' high |
2007-07-26 |
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bev pose la question :
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
Penny Nom lui répond. |
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Multiplcation of two negative numbers |
2007-07-26 |
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Brett pose la question :
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
Stephen La Rocque and Harley Weston lui répond. |
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A cone with two fruits |
2007-07-26 |
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Meg pose la question :
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?
Stephen La Rocque lui répond. |
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Cubic metres of topsoil |
2007-07-25 |
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Laurie pose la question :
How do I convert cubic meters to square meters?
Harley Weston lui répond. |
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Simplifying an algebraic fraction expression |
2007-07-25 |
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Jessica pose la question :
How do I simplify b/(b2-25) + 5/(b+5) - 6/b?
Stephen La Rocque lui répond. |
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Guessing multiple choice answers |
2007-07-24 |
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carla pose la question :
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
Stephen La Rocque lui répond. |
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Countable and uncountable sets |
2007-07-24 |
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Mac pose la question :
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 ?
Harley Weston lui répond. |
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Area of a star in a regular pentagon with side length 10cm |
2007-07-24 |
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Chetna pose la question :
A regular pentagon with side 10 cm has a star drawn within (the vertices match).
What is the area of the star?
Stephen La Rocque lui répond. |
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(1 - i)^5 |
2007-07-24 |
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sofia pose la question :
Compute the given arithmetic expression and give the answer in the form a + bi where a,b element in R.
1. (1 - i)^5
Harley Weston lui répond. |
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A one to one function |
2007-07-24 |
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Marsia pose la question :
Explain what it means for a function to be one to one.
Harley Weston lui répond. |
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A complex number in polar form |
2007-07-23 |
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roland pose la question :
write the given complex number z in polar form lzl(p+qi) where lp + qil=1 for 3 - 4i.
Harley Weston lui répond. |
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Angle of depression |
2007-07-23 |
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joyce pose la question :
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?
Harley Weston lui répond. |
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8(y + 3) + 9(y + 2) = y - 3 |
2007-07-23 |
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jordan pose la question :
8(y+3)+9(y+2)=y-3
Penny Nom lui répond. |
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Equality of sets |
2007-07-23 |
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Mac pose la question :
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 ?
Penny Nom and Harley Weston lui répond. |
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What are the dimensions of the field? |
2007-07-23 |
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Debourah pose la question :
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?
Penny Nom lui répond. |
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