One solution to Exercise 2.12:
(define (make-center-percent c p)
(make-center-width c (* c (/ p 100))))
(define (percent i)
(* (/ (width i) (center i)) 100))
One solution to Exercise 2.12:
(define (make-center-percent c p)
(make-center-width c (* c (/ p 100))))
(define (percent i)
(* (/ (width i) (center i)) 100))