how many integers from 101 to 200 , inclusive , are divisible by 3 but not divisible by 7 ?
"we should find # of integers divisible by 3 but not by 3 * 7 = 21 . # of multiples of 21 in the range from 101 to 200 , inclusive is ( 189 - 105 ) / 21 + 1 = 5 ; 33 - 5 = 28 . answer : c ."
divide(200, const_10)