We need to first simplify the ratio of blueprint to wall, of a ratio of 1 on the blue print to x in the real wall. This can be done by multiplying by the denominator, which is 4. 1/4 x 4 = 1, 3 x 4 = 12. Our new ratio is 1 to 12. If 1 = 5, then we need to multiply both sides by 5.
5 x 12 = 60.
60" on the real wall.
