; number of divisors in a range
(define (f x y n)
(- (quotient (- y 1) n)
(quotient x n)))
(display (f 100 200 7)) (newline)
(display (f 100 200 40)) (newline)
(display (f 100 200 10)) (newline)
(display (f 105 200 7)) (newline)
(display (f 105 112 7)) (newline)