Three integers are chosen at random from the first 20 integers. The probability that their product is even is

Question

Philoid · Accepted Answer

3 integers out of 20 can be chosen in ²⁰C₃ ways.

As in first 20 integers, 10 are even.

To have the product of 3 integer even the chosen integers must be even.

∴ 3 integers that are even can be chosen from first 20 integers in ¹⁰C₃ ways.

∴ Probability =

Our answer matches with option (a)

∴ Option (a) is the only correct choice