Question

solve for K
Its urgent​

Answer 1

"Four digit numbers" does not allow leading zeros, so consider 1000 - 9999. If repetition is allowed, then every number ending with either 0 or 5 is divisible by five. There are 9000 values and 2 out of 10 (or 1 out of 5) of them are divisible by 5, so 9000/5 = 1800 are divisible by 5 -- if repetition is allowed."Four digit numbers" does not allow leading zeros, so consider 1000 - 9999. If repetition is allowed, then every number ending with either 0 or 5 is divisible by five. There are 9000 values and 2 out of 10 (or 1 out of 5) of them are divisible by 5, so 9000/5 = 1800 are divisible by 5 -- if repetition is allowed.