GMAT Practice Question: An airline passenger is planning a trip that involves three connecting flights that leave from...
Question
An airline passenger is planning a trip that involves three connecting flights that leave from Airports A, B, and C, respectively. The first flight leaves Airport A every hour, beginning at 8:00 a.m., and arrives at Airport B 2 \frac{1}{2} hours later. The second flight leaves Airport B every 20 minutes, beginning at 8:00 a.m., and arrives at Airport C 1 \frac{1}{6} hours later. The third flight leaves Airport C every hour, beginning at 8:45 a.m. What is the least total amount of time the passenger must spend between flights if all flights keep to their schedules?
- 25 min
- 1 hr 5 min
- 1 hr 15 min
- 2 hr 20 min
- 3 hr 40 min
Topics: word problems, conversions, calculations, remainders
Solution
Step 1
We convert the mixed numbers into decimal hours.
2+\frac{1}{2}=2.5 1+\frac{1}{6}\approx1.167
Step 2
We note that flights from A depart every hour starting at 8:00 and take 2.5 hours to reach B.
t_{A,\text{dep}}=8+n t_{B,\text{arr}}=t_{A,\text{dep}}+2.5
Step 3
We observe that arrivals at B occur 30 minutes past the hour and that the next departure from B is at 40 minutes past the hour, so the wait is 10 minutes.
\text{arrival minutes}=30 \text{next departure minutes}=40 \text{wait}_B=40-30=10\text{ minutes}=\frac{1}{6}\text{ hour}\approx0.167
Step 4
We calculate the flight time from B to C as 1.167 hours, which is 1 hour 10 minutes.
1+\frac{1}{6}\approx1.167\text{ hours}=1\text{ hour }10\text{ minutes}
Step 5
We find that an arrival at C happens 40 minutes past the hour plus 10 minutes of flight, giving 50 minutes, and the next departure from C is at 45 minutes past the hour, so the wait is 55 minutes.
\text{arrival minutes at C}=40+10=50 \text{departure minutes at C}=45 \text{wait}_C=(60-50)+45=55\text{ minutes}\approx0.917\text{ hours}
Step 6
We sum the waits at B and C to get the total layover time.
10+55=65\text{ minutes}=1\text{ hour }5\text{ minutes}
Answer
1 hour 5 minutes
