Question

how many 7_digit numbers are there in all?​

Answer 1

Answer:

There are 90,00,000 (90 lakh) 7 digit numbers.

Step-by-step explanation:

We have 10 digit to use to make 7 digit numbers. But in first place we can not use digit 0 as if 0 is used we get 6 digit number. So, for first place we only have 9 digits and for last 6 places we have 10 digits.

Thus we get,

No of 7 digit nos = 9 × 10 × 10 × 10 × 10 × 10 × 10 = 9 × 1000000

                             = 9000000

Therefore, There are 90,00,000 (90 lakh) 7 digit numbers.

# Mussu❤