How many 6-digit numbers are even or are divisible by 5?

Answer 1

how many 6 digit numbers are divisible by 2 or 5?

that's hundred thousands only? unless you count some zeros in the front end, like 000,002.

so, go with the 100,000 to 999,999 range

half of 100,000 to 1,000,000 are divisible by 2 minus 1

that's 449,999 divisible by 2

but add in those divisible by 5 that's 1/5 of 100,000 to 1,000,000 minus 1

or 179,999

add 449,999+ 179,999 = 679,998

but subtract the overlap. It might help to do a Venn diagram

679,998-overlap =