Two friends compete with each other and five other, equally good, violinists for first and second chair in an orchestra, in a blind competition What is the probability that the two friends end up as first and second chair together?

0.0476

Step-by-step explanation:

Given : Two friends and 5 other people compete with each other for first and second chair in an orchestra.

Total people in this competition= 2+5=7

By permutation , Number of ways to arrange 7 people= 7!

Also, number of ways for two friends end up as first and second chair together= 2 × 5!   [ 2 ways to arrange friends on first and second chair and 5! ways to arrange others]

I.e. Required probability =

Hence, the probability that the two friends end up as first and second chair together = 0.0476

the sum of the lengths of any two sides of a triangle is greater than the length of the third side. if you take the three sides of a triangle and add them in pairs, the sum is greater than (not equal to) the third side. if that is not true, then it is not possible to construct a triangle with the given side lengths.

step-by-step explanation: