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Finding the nth term in fractions |
2006-01-23 |
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Zarina pose la question :
Each term in this sequence is made by increasing the numerator by 1 and the denominator by 3. here are the first five terms:
1/4, 2/7, 3/10, 4/13, 5/16, ...
(a) write an expression for the nth term:
Penny Nom lui répond. |
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A circle problem |
2006-01-23 |
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Matyan pose la question :
Find the standard equation of the circle that passes through the points (0,4) and (3,7) with center on the line
2x-y+4=0.
I've tried substituting the two points to the general equation of a circle, but I can't solve it without a third equation. The problem here is I don't really know how to use the given line of 2x-y+4=0. Please help. Thank you.
Penny Nom lui répond. |
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The three angles in a triangle |
2006-01-23 |
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A student pose la question :
the measure of the 2nd angle in a triangle is 4 more than the measure of the 1st angle. the measure of the 3rd angle is eight more than twice the measure of the 1st angle. find the measure of each angle.
Penny Nom lui répond. |
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exposant négatif |
2006-01-23 |
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Jean pose la question :
je suis un grand-père qui veut aider sa petite fille :
niveau 4ème
3 exposant -2 =
-3 exposant -4 =
3 exposant -9 =
Je vous remercie de votre aide.
Corldialement.
Jean
Claude Tardif lui répond. |
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Two parallel lines |
2006-01-22 |
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Marbara pose la question :
On my math homework I have a problem where it says find the value of x so that L is parallel to M
on one of the there are three lines. the top one is horizontal which is L. the bottom one is also horizontal directly under L which is M. there is another line that is diagonal going through the middle sections of L and M.
To the right of the diagonal line and right under line L is an equation 5x-10
to the right of the diagonal line and right above line M is an equation 8X-5
I tried to find what X is but I can't because it never matches both equations no matter what way I try to do it.
Penny Nom lui répond. |
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The angles in a hexagon |
2006-01-22 |
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Linda pose la question :
My problem is in relation to wood and making a six sided object from it. On my saw, there is a place to set the angle to which you wish to cut. I cannot for the life of me, figure this out. I am starting with a piece of plywood (1/4" x 6" x 18") and need to know what the angle degree would be to make each of the sides match perfectly to form a hexagon. Trial and error just is not working. Can someone help me?
Penny Nom lui répond. |
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A trigonometric identity |
2006-01-22 |
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Sarfaraz pose la question :
Prove the following trigonometric identity.
sin2x = tan2x/(1+tan2x)
Penny Nom lui répond. |
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A binomial distribution exercise |
2006-01-21 |
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Belinda pose la question :
In a survey of 15 manufacturing firms, the number of firms that use LIFO (a last-in first-out accounting procedure for inventory) is a binomial random variable x with n=15 and p=0.2.
a) What is the probability that five or fewer firms will be found to use LIFO? Is it unlikely that more than 10 firms will be found to use LIFO? Comment.
Penny Nom lui répond. |
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A confidence interval |
2006-01-21 |
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Jonathan pose la question :
I am attempting to calculate how my confidence interval will widen at the 95% confidence level if my response universe increases from 100 to 150 or to 200.
There is a universe of 54,000. I take a 5% sample for a test universe of 2,700
If my "yes" universe is 100, at the 95% confidence level, what is my +/- range? (i.e +/- 3? +/-5?)
Historically, 6.6% of the 2,700 you say "yes". I am trying to determine how the confidence interval would change if the number of "yes" responders increased to 150 or to 200.
Penny Nom lui répond. |
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1/3 of 1/4 |
2006-01-21 |
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Nicole pose la question :
WHAT FRACTION IS EQUAL TO 1/3 OF 1/4
Penny Nom lui répond. |
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Markups and discounts |
2006-01-21 |
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Dan pose la question :
I'm trying to increase my pricing by 30 percent. I'm doing something completely wrong. If my price is $150.00 and I increase the price by 30 percent. I would take 150 times .30 and that equals 45. I would then take 45 plus 150 and that would give me 195. My problem is now 195 is my list price. If I turn around and give my customer a 30 percent discount off the 195 the price ends up being 136.50. Which is less than the 150 that I started with. I'm confusing myself and have totally lost confidence in what I'm doing and how . Can you help me?
Penny Nom lui répond. |
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Converting units |
2006-01-21 |
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A student pose la question :
How can you solve a measurement problem by changing it to a fraction of the new unit that follows such as:
18 inches =------------------- yard
40 minutes = -------------- hour
5 days = -------------- week
Penny Nom lui répond. |
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The circumference of a larger circle is twice the circumference of a smaller circle. |
2006-01-20 |
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Amanda pose la question :
The circumference of a larger circle is twice the circumference of a smaller circle. What is the ratio of the radius of the smaller circle to the diameter of the larger circle?
Penny Nom lui répond. |
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One boundary of a pond is parabolic in shape. |
2006-01-20 |
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Glenn pose la question :
One boundary of a pond is parabolic in shape. The boundary passes through the points A(-20,45), B(40,40) and E(30,35). The equation of the parabola is of the form y=ax2+bx+c. Find the equation of the parabola and the coordinates of the vertex of the parabola. Any assistance you could provide would be greatly appreciated.
Penny Nom lui répond. |
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An irregular octagon |
2006-01-20 |
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Robert pose la question :
I am building a poker table which is in the shape of an irregular octagon. I know the table measures 72 inches long and 48 inches wide with two parallel straight sides of equal length and six smaller sides of equal length ( three at each end of the table), what I don't know are the lengths of the any of the sides.
Harley Weston lui répond. |
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