How many 3 digit counting numbers less than 800 have digits that are all even?

1 Answer
Dec 2, 2016

75

Explanation:

Considering the possible values of each digit in turn:

First digit {2, 4, 6} Since the number < 800 (Assuming a leading 0 is not allowed) = 3 possibles

Second digit {0, 2, 4, 6, 8} = 5 possibles

Third digit {0, 2, 4, 6, 8} = 5 possibles

Hence the number of 3 digit numbers in NN < 800 where all digits are even is:

3xx5xx5= 75