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An octagon inscribed in a circle 2002-01-10
Kent pose la question :
A circle of 30 in. diameter has an octagon (8 equal chords) inscribed in it. What is the length of each chord?
Chris Fisher lui répond.
Nickles, dimes, quarters and fifty cent pieces 2002-01-08
A parent pose la question :
The total for all coins counted is $4,564.50 The last coin added to the pile is a 50 cent piece There are 8 times as many 50 cent pieces as there are quarters There are 6 times as many dimes as nickles How many of each are there?
Penny Nom lui répond.
All of the Christmas trees are fifty-five percent off. 2002-01-08
A teacher pose la question :
All of the Christmas trees are fifty-five percent off. Madison bought a tree and paid $103.50. Assuming no tax, what was the original price of the tree?
Penny Nom lui répond.
Ses points de discontinuités est les irrationnelles 2002-01-08
Un eleve pose la question :
Je voudrait montrer qu'il n'existe pas de fonction de R--->R tels que ses points de discontinuités est les irrationnelles, en utilisant la methode de "baire".
Claude Tardif lui répond.
Maple trees and pine trees 2002-01-06
A student pose la question :
A team of scientists found that in a forest there was four maple trees for every nine pine trees.How many maple were there if they counted 45 more pine than maples?
Penny Nom lui répond.
Catenary 2002-01-02
Jason pose la question :
I am a high school math teacher. I was asked by a friend who is in architectural design for a method for determining the volume of what he called a Catenary.

The Catenary curve is modeled by the equation y=a cosh(x/a). I ran into a mess when I tried to compute the volume of the solid formed by revolving that curve around the y-axis.

Any help you can provide would be greatly appreciated.


Harley Weston lui répond.
Isoperimetric quotients 2002-01-02
A student pose la question :
I'm stuck on my GCSE Maths coursework, what do isoperimetric quotients measure?
Penny Nom lui répond.
2/3 vs 3/4 2002-01-02
Julia pose la question :
So, here's my question. Some of the problems they've had to do starts off with two fractions, and they have to tell whether the two fractions are:
  1. The first one is greater than the second one
  2. The first one is less than the second one, or
  3. They are equal.

One day my son had the problem of 2/3 vs 3/4. Without drawing out a pie chart, how in the world can a child "eyeball" a problem like this and tell what the correct answer is? I've also tried to teach about making common denominators, but that's going over his head at this point.


Denis Hanson and Harley Weston lui répond.
Fractions to decimals and percents 2001-12-31
A student pose la question :
2/5 , 4/8 , 4/10 , 3/5 , 6/8 , 7/7 (what is the decimal and percent for each)

1/5 , 1/10 , 1/8 , 1/1 (what is the decimal for each)

100 PERCENT, WHAT IS THE DECIMAL?

The ratio of boys to girls in a class is 1:4. What percent of the class are girls?

Penny Nom lui répond.
A hyperbola centered at (0,0) 2001-12-28
Carla pose la question :
  1. Find the equation of the hyperbola centered at (0,0) with vertices at (0,3) and (0,-3) that is asymptotic to the lines y=+-5x.

  2. Find the equation of a hyperbola in standard position foci (1,5) and (1,7) and eccentricity 2.

Peny Nom lui répond.
Two algebra problems 2001-12-24
Cass pose la question :
if the graph of a equation is 2x2 - y2 = 8 passes through point (6,k), find the positive value of k.

if 5x2 - 2 x = 1, find positive value of x


Penny Nom lui répond.
The probability that the area of a triangle is smaller that 1/8 2001-12-21
Hoda pose la question :
Given unit square pick two points on adjacent sides of the square , what is the probability that the area of the resulting triangle is smaller that 1/8? I tried to tackle the problem by first sketching a square with the four vertices at (0,0), (1,1), (0,1) and (1,1). The answer seems to be the area under the curve y=0.25/x between 1 and 0, but how can you integrate such a function when ln0 is undefined? any help would be highly appreciated.
Andrei Volodin lui répond.
Feeding Jumbo 2001-12-21
Lupe pose la question :
There are 2 dogs one named major and the other jumbo. major weighs 100 pounds and jumbo 150 pounds. they eat dry dog food which comes in a 40-pound bag that cost $30. Together, major and jumbo eat a whole bag a week. major eats two fifths of the bag while jumbo eats the rest.How much would it cost to feed jumbo in february, which has 28 days?
Penny Nom lui répond.
450 students 2001-12-19
Jessie pose la question :
My teacher told me that the number of ways of lining up the 450 students in our school is larger than the number of atoms in the universe. Is this right?

This question came to Good Question, a regular feature on the CBC Morning Edition radio show in Saskatchewan.


Denis Hanson and Harley Weston lui répond.
Getting to B in the shortest time 2001-12-19
Nancy pose la question :
A motorist in a desert 5 mi. from point A, which is the nearest point on a long, straight road, wishes to get to point B on the road. If the car can travel 15 mi/hr on the desert and 39 mi/hr on the road to get to B, in the shortest possible time if......

A.) B is 5 mi. from A

B.) B is 10 mi. from A

C.) B is 1 mi. from A


Penny Nom lui répond.
 
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