Answer:
x = 12 miles
Step-by-step explanation:
Sarah can walk 3 miles in 1 hour.
At this pace how many miles will Sarah walk in 4 hours?
Write and solve an equation of ratios:
3 mi 1 hr
--------- = --------
x 4 hr
Cross-multiplying yields x = 12 miles.
Sarah can walk 12 miles in 4 hours
