Question

You paint 12 wall in 14 hour. At that rate, how long will it take you to paint one wall?

Answer 1

for 12 wall it takes = 14 hr
for one wall = 14*1 /12 =

Answer 2

or you can set it up as a proportion :
12/14 = 1/x (12 walls to 14 hrs = 1 wall to x hours)
cross multiply
(12)(x) = (14)(1)
12x = 14
now just solve for x