If all multiples of 3 and all multiples of 4 are removed from the list of whole numbers 1 through 1200, then how many whole numbers are left?
+538 There are 1200/3=400 multiples of 3 and 1200/4=300 multiples of 4 makings 7. But we also have to account for the numbers that are in both sets, which are all the multiples of 12. 1200/12 is 100. So the number of multiples of 3 and 4 between 1 and 1200 should be 300+400-100 or 600. There are 1200 numbers through 1-1200, so 1200-600=
600 numbers remaining.
