(- 100 (* 7 (+ 8 (/ -12 -3))))
100 - (7 * (8 + (-12/-3))) = 16
> (/ 10) 0.1
1/10 = 0.1
> (/ 30 5 2) 3
5*2 = 10 /30 10 30/10 = 3
> (- 10 1 2 3) 4
10 -1 - 2 -3 = 4