if a person walked 3/4 mile in 12 minutes . how long would it take to walk three miles at this pace

Answer 1

3/4/(12) = 3/4*1/12 = 3/48 = 1/16 mi/min.
3/(1/6) = 3 * 6/1 = 18 min.

Answer 2

x/3 = 12/(3/4) = 12 * 4/3 = 48 min