Find number of four-digit numbers in which repetition is not allowed.

Find the number of three-digit number in which repetition is allowed and sum of digits is even.

Find the number of three-digit number in which repetition is allowed and sum of digits is even.

Find the number of three-digit number in which repetition is allowed and sum of digits is even.

Find the number of three-digit numbers (repetitions allowed) such that at least one of the digitsis 9

The number of 3 digit odd number, when repetition of digits is allowed is

X is the number of two-digit numbers formed by 3, 5, or 7, when the repetition is allowed. Y is the number of two-digit numbers formed by 3, 5, or7, when the repetition is not allowed. Find by how much X exceeds Y.

How many four digit odd number are there ? (Repetition of digit is not allowed )

A two digit number is formed with the digits , 2,5,9 ( repetition is allowed ) . Find the probability that the number is divisible by 2.