SOLUTION: How many positive integers are there less than 800 such that all digits are even?

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Question 1019457: How many positive integers are there less than 800 such that all digits are even?
Found 2 solutions by Alan3354, richard1234:
Answer by Alan3354(69443) About Me  (Show Source):
You can put this solution on YOUR website!
How many positive integers are there less than 800 such that all digits are even?
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That's 3 digit numbers 000 to 800
Are leading zeroes accepted? eg, 008?

Answer by richard1234(7193) About Me  (Show Source):
You can put this solution on YOUR website!
We can assume leading 0's are allowed since we also want 1- and 2-digit numbers (e.g. 086 equals 86, and 002 = 2).

The hundreds digit can be 0,2,4,6 (4 choices), and the tens and units digit can be 0,2,4,6,8 (5 choices each). Multiplying, we get 4*5*5 = 100. However this includes 000 which isn't positive, so the total number of such integers is 99.