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Children and probability |
2002-01-16 |
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From Bill:
If a family has four children, what is the probability that all 4 are the same sex?
Answered by Vanrei Volodin. |
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Negative exponents |
2002-01-16 |
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From Julie:
If z to the power of -4= 1/z4 then how would you solve 1/t-2?
Answered by Penny Nom. |
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Linear regression |
2002-01-16 |
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From Murray:
If you have a set of coordinates (x[1],y[1]),(x[2],y[2]),...,(x[n],y[n]),find the value of m and b for which SIGMA[from 1 to m=n]AbsoluteValue(y[m]-m*x[m]-b) is at its absolute minimum.
Answered by Harley Weston. |
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50% |
2002-01-15 |
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From Lakarrieh:
4 is 50% of what number?
Answered by Penny Nom. |
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What is a group of three numbers called in a large number? |
2002-01-15 |
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From Laurie:
What is a group of three numbers called in a large number? My son has this question on his 4th grade worksheet. I've taught middle school math for 7 years and nver heard of it.
Answered by Paul Betts. |
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8% tax |
2002-01-15 |
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From A student:
total price including tax is $13359.60
8% tax was paid
What is the dollar amount of tax paid?
Answered by Penny Nom. |
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Algebra review questions |
2002-01-14 |
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From A student:
- A wildebeast was observed racing a distance of 86.4m in 4.8 seconds. Find the speed of the wildebeast in m/s.
- 8x - 7 - 5x = 23
- 7 z - 3 (z + 2) = 26
Answered by Penny Nom. |
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Adding vectors |
2002-01-12 |
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From Lena:
how do you add vectors together?
If you are given the length and angles of both vectors and are asked to add/subtract them, how do you do it? I know you are supposed to do the head to tail method, but whenever i try it i get the wrong answer. I need help setting it up. example: A is 2.7cm, and 60 degrees, B is 1.6cm and 135 degrees, find the magnitude and amplitude
Answered by Penny Nom. |
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The tangent function |
2002-01-12 |
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From Justine:
if you know that sin45degress = cos45degrees, how do you know that tan45degrees = 1?
Answered by Penny Nom. |
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The famous "train problem" |
2002-01-12 |
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From Karen:
How do you solve the famous "train problem"? For example, 2 trains leave different stations at the same time. One is traveling at 50 mph and the other at 40 mph. How long does it take them to meet?
Answered by Penny Nom. |
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Papy's Computer |
2002-01-11 |
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From Mary-Anne:
My second-grade son brought home a fun math worksheet which involved calculating sums using "Papy's Computer." I had never heard of this before and found it to be quite interesting. Each digit in a decimal number is represented by a 2x2 grid. Each grid square corresponds to one of the numbers 1,2,4, or 8.
Answered by Harley Weston. |
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Why do integers have the symbol of Z? |
2002-01-11 |
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From Stephanie:
Why do integers have the symbol of Z? Natural numbers have the symbol of N, whole numbers have the symbol of W. Our professor has asked us to find out why the letter Z is represented for integers.
Answered by Penny Nom. |
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A sequence of number pairs |
2002-01-10 |
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From Terry:
Three is the first number of a pair, and 8 is the second.
a. If 50 is the first number, what is the second number?
b. If 200 is the first number, what is the second number?
c. If 89 is the second number, what is the first number?
d. If a number n is the first number, what is the second number?
3-8
4-11
5-14
6-17
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10-29
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Answered by Peny Nom. |
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Glasses of wine |
2002-01-10 |
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From A student:
6 glasses of regular wine (12% alcohol) would equal aprox.? glasses of wine (8% alcohol)
a)9.33
b)8.5
c)7.75
d)9.0
Answered by Peny Nom. |
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A simplification problem |
2002-01-10 |
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From A Parent:
FIND (A / B) . (C / D)
where
A = Y squared + 3 . Y cubed
B = Y squared + 4
C = 2 . Y + Y squared
D = Y + 4 Y squared + 3 Y cubed
Answered by Penny Nom. |
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