What is this answer?

hello from mrbilldoesmath!

answer:

104 f = 40 c

discussion:

9/5c + 32 = f               => in our case, f = 104

9/5c + 32 = 104           => subtract 32 from both sides

9/5c         = 104 - 32   =>

9/5c   = 72                   => multiply both sides by 5/9 (the reciprocal of 9/5)

(5/9)*(9/5) c = 72 * (5/9) =>

c = 72*5/9 = 360/9 = 40

you,

mrb