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A percent as a fraction |
2007-11-24 |
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From Abby:
write 43.75% as a fraction or mixed number in lowest terms.
Answered by Penny Nom. |
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The maximum area of a rectangle |
2007-11-23 |
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From Christy:
Question from Christy, a student:
Show that among all rectangles with an 8m perimeter, the one with the largest area is a square.
I know this is simple but I'm not sure if I'm doing it correctly. Here is what I did.
1. A = xy
2. 8 = 2x+2y
3. y = 4-x
4. A = x(4-x) = 4x-x^2
Not sure what to do from this point because I don't know if its right.
Answered by Harley Weston. |
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Dividing a circle |
2007-11-23 |
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From matt:
hi. can you please send me a diagram of how to draw 3 lines in a circle to get 8 sections.
Answered by Stephen La Rocque. |
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Ordering fractions |
2007-11-23 |
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From Joy:
what are the orders of these fractions?
2/3, 1/2, 1/4, 2/10, 3/4, 1/3, 9/10, 2/2.
Answered by Penny Nom. |
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F=4a-3c+6b |
2007-11-22 |
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From olive:
comment calcule ton ?
F=4a-3c+6b
mon fils et en 4ème et je suis dépassée, je ne peut pas l'aider
merci de le faire à ma place.
Answered by Claude Tardif. |
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A curve sketch |
2007-11-22 |
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From Ahson:
Find critical points, determine the monotonicity and concavity and sketch
a graph of f(x) with any local maximum, local minimum and inflection
points labeled:
1. f(x) = x^4 - x^3 - 3x^2 + 1
Answered by Harley Weston. |
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The definition of the sine function |
2007-11-22 |
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From Indrajit:
I need a explanation in this theory.......if sinθ = p/h...then
sin 90 deg. = p/h
or 1 = p/h
or p=h .....how can a perpendicular be equal to a hypotenuse.???
Answered by Harley Weston. |
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How many marshmallows did I use? |
2007-11-21 |
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From gloria:
the # of marshmallows i use is an even # .it is 2 digit number more than 10 less than 20 the 10th digit half of one digit.how many marshmallows did I use?
Answered by Chris Langdon. |
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How many devices fit in a sq foot? |
2007-11-21 |
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From JB:
We buy product in rolls: 54" x 150'. We make a product that is 2 x 3.5 inches out of this roll and sell by the each. How do we convert this? What is the formula to determine how many devices fit in a sq foot. Then we / by 12? PLEASE help. Thank You.
Answered by Victoria West. |
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Area of a 17-sided lot |
2007-11-21 |
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From Lynda:
My uncle is wanting to buy this piece of land [a 17-sided polygon] but we are questioning the acerage total. the measurements are [on the attached diagram].
Answered by Stephen La Rocque. |
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A 4 by 4 magic square |
2007-11-21 |
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From sue:
This is for my 10 year old nephew. His math question is: he has a 4X 4 magic square. The top squares are from left to right: 359,356,353,366. He says that columns are supposed to equal 796. We can't figure it out and would really appreciate any help we could get.
Answered by Penny Nom. |
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What is the sum of the reciprocals? |
2007-11-21 |
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From anya:
the sum of two numbers is 32, and the product of these 2 numbers is 48. what i sthe sum of the reciprocals of the 2 numbers? Express answer as a common fraction
Answered by Penny Nom. |
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A right triangle |
2007-11-21 |
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From Jason:
One leg of a right triangle is 12 inches long. The other leg is 3 inches
shorter than the hypotenuse. Find the lenght of the hypotenuse.
Answered by Penny Nom. |
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20 gallons of concentrate |
2007-11-20 |
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From Ken:
What is the formula I need to use?
I have 20 gallons of concentrate. I am mixing it at 0.5%.
How many total gallons of solution will I end up with?
I came up with 4000 gallons of solution - but not using the easiest of methods.
Answered by Penny Nom. |
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A t-test |
2007-11-20 |
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From Rachel:
I am wanting to use the t-test to find if temperature over a period of 5 days was significantly different to the mean temperature for that time of year. So i want to compare expected temps to actual temps. The problem is that because the expected temperature is the same for the 5 days it gives me a standard deviation of zero. Does this mean the t-test cannot be used because the f-test can't be calculated. If so is there an alternative test?
Answered by Harley Weston. |
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