Question

Find the total number of seven digit numbers so that the sum of digits is even

Answer 1

Answer:

9999999 - 1000000

Answers : (1)

So total number of 7 digit numbers=9999999 - 1000000+1). Out of 9000000 numbers 4500000 are having the sum of digits as even and the remaining 4500000 are having the sum of digits as odd. SinceEvery alternate number has its sum of digits even and odd. So the required answer is 4500000.