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La limite de (x(n)) |
2002-10-01 |
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From Une étudiante:
3) Soit L, le point ayant pour abscisse la limite de (x(n)) a) Exprimer la distance M(n)L en fonction de n b) Déterminer le plus petit entier naturel n(o) pour lequel la distance Mn(o)L est inférieur à 0,01 c) Justifier alors qu'à partir du rang n(o), tous les points M(n) sont situés dans le segment de centre L et de rayon 0,0 1
Answered by Claude Tardif. |
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Two rate problems |
2002-09-30 |
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From Rebecca:
- There are two small holes in the bottom of a tub filled with water. If opened, one hole will empty the tub in three hours; the other will empty it in six hours. If both holes are opened at the same time, how long will it take to empty the tub?
- An airplane flies 400 miles per hour in calm air. It can cover 900 miles flying with the wind in the same time that it can cover 700 miles against the wind. What is the speed of the wind?
Answered by Penny Nom. |
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Comment fait on pour justifier que... |
2002-09-30 |
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From Lucie:
Comment fait on pour justifier que p au carré est égal à 2 fois q au carré?
Answered by Claude Tardif. |
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A geometry problem |
2002-09-29 |
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From Sonia:
Given AB||CD; m a. Find the measures of
b. Is there enough information for you to conclude that
Answered by Penny Nom. |
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0.99999... |
2002-09-26 |
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From Erica:
Yesterday in my 8th grade math class we were being taught how to convert a Repeating Decimal into a fraction. Since I, for some odd reason, seem to understand math better than the rest of my classmates, i began to drown out my teachers explaination for the rule. While she was about half way through with explaining mixed decimals i came up with an unsolvable question. Like I said before, I understand how to turn a repeating decimal into a fraction, but how would I turn a repeating .9 into a fraction? We all know it would equal 9/9, but doesn't 9 over 9 also equal 1? Even though it comes very close to one, it never really equals one. I'm very confused about this and i would love it if you could clear this up for me.
Answered by Penny Nom. |
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Proof by induction |
2002-09-26 |
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From Pooh:
Use induction to show that
1 2 + 2 2 + .....+n 2 = (n 3)/3 + (n 2)/2 + n/6
Answered by Paul Betts. |
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Painting a car |
2002-09-24 |
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From A student:
Dan can paint a car in 4 hours. Luke can pain the same car in 6 hours. Working together, how long would it take them to pain the same car?
Answered by Penny Nom. |
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Number play |
2002-09-24 |
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From Julie:
Organize these numbers and the operations so that each equation is correct. Use each coice only once per equation.
36 18 12 6 - + ( ) /
_________________________ = 22
_________________________ = 41
Answered by Claude Tardif. |
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Dividing fractions |
2002-09-23 |
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From Angie:
When I was taught to divide a fraction, I was told to multiply the reciprocal. Many times I find I can just divide the fraction, and it saves all the simplifying after. For example, 4/6 x 9/14 divided by 2/4 I would say 4x9divided by 2=18 over 6x14divided by 4 =21, so the answer is 18/21 but if I multiply the reciprocal, I would end up with 4x9x4 over 6x14x2 which equals 144/168. So, why are we taught to do it this way? Is it necessary?
Answered by Chris Fisher. |
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A cone that is cut off at the top |
2002-09-23 |
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From Stuart:
I have to work out the dimensions and arcs of a cone that is cut off at the top. I.e Top diameter is 33mm to bottom diameter is 43mm and the depth is 80mm Are you able to work what the flat of this cone would be as I need to design within the flat area and then have it cut out. I really need to know what the flat of it is before it is cut and curled to form the above cone.
Answered by Walter Whiteley. |
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Solving an equation |
2002-09-22 |
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From Emanuel:
how do u solve these problems?:
30/x=7+ 18/2x
3m+1/4 = 2- 3-2m/3
Answered by Penny Nom. |
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Ceiling |
2002-09-22 |
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From Joe:
Does the ceiling of a number mean the ceiling of 1.3 is 2 and
the ceiling of 1.5 is 2 and
the ceiling of 1.8 is 2. Or the ceiling of 1.3 is 1.5?
Answered by Penny Nom. |
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A max/min problem |
2002-09-21 |
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From Evelina:
A window is the shape of a rectangle with an equilateral triangle on top. The perimeter of the window is 300 cm. Find the width that will let the maximum light to enter.
Answered by Penny Nom. |
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Fractional exponents |
2002-09-20 |
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From Jill:
The problem is with fractional exponants:
10 1/3 mult. by 10,000 The 1/3 is an exponant of 10.
Answered by Penny Nom. |
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The entire earths' population would fit in the state of Texas |
2002-09-18 |
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From Roz:
I have been told that the entire earths' population would fit in the state of Texas and each person would have 1/2 acre. Is this true.
Answered by Chris Fisher. |
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