I think my and irspow's methods are pretty much the same, just worded differently. We get the same answer, anyway.

Don't worry, you're in your own spot. Our spots just happen to look similar.
Anyway, I think we're right. Ganesh told us that the bolt was defective, and wanted to know tha probability of it being from B.

k+90's formula is:

Problem # k + 91

Find three consecutive terms in Geometric Progression such that their sum is 21 and the sum of their squares is 189.

mathsyperson's solution to problem # k + 91 is correct. I shall post the method if none of the others are able to give a proper solution with the steps.

Problem # k + 92

If x=9 + 4√5, find the value of √x - 1/√x.

Problem # k + 93

A right ciruclar cone is cut by two planes parallel to the base, trisecting the altitude. What is the ratio of the volumes of the three parts, the top, middle and the bottom respectively?

Well done, mathsyperson!



Problem # k + 94

If 1/a + 1/b + 1/c = 1/(a+b+c); a+b+c≠0 and abc≠0, what is the value of (a+b)(b+c)(c+a)?

This is not my type of problem, but here goes nothing.

Last edited by irspow (2006-02-20 00:14:16)

Problem # k + 95

1 man or 2 women or three boys can do a work in 55 days. In how many days can 1 man, 1 woman and 1 boy do the same work?

k+95:
1m-1/55 per day
1w-1/110 per day
1b-1/165 per day
t-the numbers of days:
t(1/55+1/110+1/165) = 1;
t(1/30)=1;
t=30 days.

Yeah

Problem # k + 96

Can a majority of the numbers from 1 to a million be represented as the sum of a square and a (non-negative) cube?