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A 5% increase |
2005-04-27 |
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Debra pose la question :
How can I determine the increased percentage of a dollar amount? I.e.: One dollar amount is $202 and another is $150, how can I determine the 5% increase from last year on the $202 dollar amount?
Claude Tardif lui répond. |
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Cubic yards of sand |
2005-04-27 |
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Renee pose la question :
I need to find out how much sand I would need to order for the base of a horse round pen. The pen is 40 ft across and I would like a depth of 4 inches. I have to order the sand in cubic yards.
Penny Nom lui répond. |
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Un repère orthonormal |
2005-04-26 |
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Ylène pose la question :
Dans un repère orthonormal, le point A a pour coordonnées (-2;3) et le point B a pour (4;-5). A partir des coordonnées des points A et B on propose les calculs suivants:
a/ (-2+4 sur 2 ; 3-5 sur 2)
b/ (4+2; -5-3)
c/ racine carré (4+2)²+(-5-3)²
dans chaque cas, quelle est la notion géométrique ainsi mise en évidence?
Claude Tardif lui répond. |
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mod n |
2005-04-26 |
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Jean pose la question :
Réecrire (5A27)en base 16 changer en base 8
( (2n)!+ 1) (mod n)
(1-764n) (mod n)
(n+1)exposant 78355 (mod n)
PPCM(n!+1 , n!)
Claude Tardif lui répond. |
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Probability and smoking |
2005-04-24 |
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Sean pose la question :
20% of a certain population smoke. For smokers the probability of dieing of lung cancer is ten times what it is for non-smokers. Over all the probability of dying of lung cancer is .006. Find the probability for smokers and nonsmokers.
Chris Fisher lui répond. |
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A pyramid |
2005-04-24 |
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Marc pose la question :
I'm helping my daughter build a pyramid,it needs to be 30cm in height. I have cut out four pieces at 30 deg angles. When I went to join up the pieces it did not fit. I re-check my measuments and found that they were correct. Do I need to cut two pieces smaller so they can match up? Did I cut them at the wrong angles. My base is also 30cm, is that my problem?
Chris Fisher and Harley Weston lui répond. |
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An isosceles triangle...with |
2005-04-23 |
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Shannon pose la question :
If given an isosceles triangle...with
Is there any possible way to do this, without knowing a side, if so, please
explain in detail.
Chris Fisher lui répond. |
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A pattern of numbers |
2005-04-21 |
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Claire pose la question :
We need to be able to discover the nth term in a pattern of numbers and
explain how we did it. We have arrived at the formula 1+2+3+...n=n(n+1)/2
for trios where a trio series is;
3 has the following trio (1,1,1)
4 has the following trios (2,1,1), (1,2,1), (1,1,2)
5 has the following trios (3,1,1), (1,3,1) (1,1,3) (1,2,2) (2,2,1) (2,1,2)
So the series is as follows
Penny Nom lui répond. |
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P(x+1)-P(x)=x |
2005-04-21 |
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Etienne pose la question :
~P(x)=a  x3+ b
x2+ c
x
~P(x+1)-P(x)=x2
question: trouver les trois nombres a,b et c.
Claude Tardif lui répond. |
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Une réduction de 40% |
2005-04-21 |
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Isabelle pose la question :
une famille composée de 3 enfants, et 2 adultes partent en expédition.
ils payent au total 80€ sachant que les enfants bénéficient d'une réduction de 40% combien payent les parents et les enfants ?
Claude Tardif lui répond. |
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The least integer of a set of consecutive integers |
2005-04-19 |
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Lucia pose la question :
The least integer of a set of consecutive integers is -25. If the sum of these integers is 26, how many integers are in the set?
Penny Nom lui répond. |
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40% profit |
2005-04-19 |
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Carol pose la question :
Could you please tell me the formula to calculate for example a 25% profit on cost.
I.e a sandwich cost .75p for the cost of ingredients, I wish to make a 40% profit on that cost so what do I multiply and divide it by to arrive at the selling price in order to achieve a 40% profit?
Penny Nom lui répond. |
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Percentage increase |
2005-04-19 |
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Tom pose la question :
What is the percentage increase from (negative -$9262.00) to (positive $3840.00)?
Penny Nom lui répond. |
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Centimeters, millimeters and milliliters |
2005-04-19 |
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A student pose la question :
How many milliliters in a centimeter?
Penny Nom lui répond. |
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A Taylor series for ln(x) |
2005-04-16 |
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Anood pose la question :
i have to represent ln(x) as a power series about 2
i`m not getting the final answer which is ln 2+ sigma (((-1)(n+1)/
(n*2n))*(x-2)n). i don`t get the ln 2 part
i show you my trial
f(x)= ln x.
f-(x)=(1/x) .
f--(x)= (-1/x2)*1/2!
f---(x)= (2/x3)*1/3!
f----(x)= (-6/x4)* 1/4!
so the pattern shows me that f(n)= ((-1)(n+1))/xn *n)
so f(2)= sigma ((-1)(n+1))/2n *n) *(x-2)n
so as you see i don`t get ln 2
Penny Nom lui répond. |
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