Class 12

Math

Algebra

Probability I

Four numbers are chosen at random (without replacement) from the set {1, 2, 3, …, 20}.

Statement 1:

The probability that the chosen numbers when arranged in some order will form an A.P. is $1/85$.

Statement 2:

If the four chosen numbers form an A.P., then the set of all possible values of common difference is ${±1,±3,±3,±4,±5}$.