Question

Find the number of integers greater than 7,000 that can be formed using the digits 4, 6, 7, 8, and 9, without repetition: ______

Options

• 216

• 192

• 120

• 72

Answer 1

192.

Explanation:

4 digit integers

1^st digit can be selected in 3 ways

∴ Total number of 4 digit integers = `3xx 4 xx 3 xx 2`

= 72

Total number of 5 digit integers = 5! = 120

∴ total number of integers = 72 + 120

= 192