Question

Using the digits 2,3,4,5,7,8 (use each digit only once) form a 4-digit number divisible by 9​

Answer 1

Step-by-step explanation:

Hence, the unit's digit in the required 4 digit number must be 0 or 5. But here only 5 is available. The remaining places can be filled by remaining digits as 5 x 4 x 3 ways. Hence, number 4-digit numbers can be formed are 5 x 4 x 3 = 20 x 3 = 60.

Answer 2

4 digit number divisible by 9 is 2457