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A combination question |
2005-01-26 |
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From Kelly:
A computer with an old processor locks up if more than 4 applications are running at the same time. If the owner has 20 applications stored in his program file, how many different sets of 4 can he run, so that his computer does not lock up?
Answered by Penny Nom. |
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un nombre entier |
2005-01-25 |
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From Un eleve:
comment démontrer qu un nombre entier est un carré parfait si et seulement si il admet un nombre impair de diviseurs?
Answered by Claude Tardif. |
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Three tangent circles |
2005-01-25 |
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From Kate:
Two circles, C1 and C2, touch each other externally; and the line l is a common tangent. The line m is parallel to l and touches the two circls C1 and C3. The three circles are mutually tangent. If the radius of C2 is 9 and if the radius of C3 is 4, what is the radius of C1?
Answered by Chris Fisher. |
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il y a 1/6 de voitures bleues, |
2005-01-24 |
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From Facrice:
il y a 1/6 de voitures bleues, 2/9 de voitures rouges, 5/12 de voitures blanches et 1/8 de voitures vertes. Sachant que 15 voitures sont d'une autre couleur. Combien y a t il de voitures de chaque couleur.
Answered by Claude Tardif. |
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Differentiating F(x,y) = 0 |
2005-01-23 |
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From Jacob:
In calculus, we often mention to the students that if F(x,y) = 0, then we can differentiate both sides and still get an equality. The problem is that we can't perform the same operation on F(x) = 0, say x = 0, otherwise 1 = 0, which is absurd. What is the reason?
Answered by Walyer Whileley and Harley Weston. |
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cos 2x = sin x |
2005-01-22 |
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From Kris:
solve the equation
cos 2x = sin x for 0<= x < 360
Answered by Penny Nom. |
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When dividing a 3-digit number by a 1-digit number... |
2005-01-22 |
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From A student:
When dividing a 3-digit number by a 1-digit number, for what divisors can you get a remainder of 8?
Answered by Penny Nom. |
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The diameter of a 800 km circle |
2005-01-22 |
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From Mechelle:
What is the diameter of a 800 km circle?
Answered by Penny Nom. |
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A 6 sided (hexagonal) pyramid |
2005-01-22 |
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From Steve:
im trying to make a 6 sided (hexagon) pyramid, from 6 triangles of 12mm plywood, i know all the angles to cut apart from the one one to join all 6 triangles together. Rough measurements are outer edge (A) of each triangle is 13cm's, length of other 2 sides (B&C) of triangle outside to center is 14cm's with a height of the whole thing together about 6cm's.
Answered by Chris Fisher and Harley Weston. |
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The area of a triangle |
2005-01-21 |
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From Amy:
In tirangle ABC, AB=6, BC=9, BC is the angle bisector of angle ABC and M is the midpoint of BD. If the area of ABC is 30, what is the area of ABM?
The height comes out greater than the hypotenuse, but the teacher said that there's an answer for it. Can you show me how? Thanks
Answered by Chris Fisher. |
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Finding the missing side of a triangle |
2005-01-20 |
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From Jason:
I found a geometry problem that reads as follows:In triangle ABC,
Answered by Penny Nom. |
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The angle between two forces |
2005-01-19 |
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From Abraham:
One force of 20 pounds and one force of 15 pounds act on a body at the same point so that the resultant force is 19 pounds. Find, to the nearest degree, the angle between the two original forces.
Answered by Penny Nom. |
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The radius of a circle |
2005-01-18 |
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From A student:
find the radius of a circle whose area is 1256sq cm.Use pi as an appoximation for pi.
Answered by Penny Nom. |
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A non-rerctangular lot |
2005-01-18 |
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From EM:
One corner of a 60X120 foot lot, otherwise rectangular, is a curve with a radius of 20 feet and a central angle of 90 degrees. What is the area?
Answered by Penny Nom. |
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The side of a cube |
2005-01-17 |
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From Jake:
I have one for you that's got me stumped. Is it possible to calculate the dimensions of a square if I have the cubic feet? Say I know the package to be 180 cubic feet.
Answered by Penny Nom. |
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