In this case, we'll have to carry out several steps to find the solution.
Step 01:
Data
t = time
f = fuel efficiency
inequalities = ?
Step 02:
1. time
t ≤ 45 min
2. fuel efficiency
f ≥ 40 miles per gallon
The answer is:
1. time
t ≤ 45 min
2. fuel efficiency
f ≥ 40 miles per gallon