A man complete a journey in 10 hours. He travels first half of the journey at…
2023
A man complete a journey in 10 hours. He travels first half of the journey at the rate of 21 km/hr and second half at the rate of 24 km/hr. Find the total journey in km.
- A.
220 km
- B.
224 km
- C.
230 km
- D.
234 km
Attempted by 9 students.
Show answer & explanation
Correct answer: B
Let each half of the journey be x km, so the total distance is 2x km.
Time equation:
Time for first half = x/21 hours
Time for second half = x/24 hours
Total time = x/21 + x/24 = 10 hours
Combine the fractions: 1/21 + 1/24 = (8 + 7)/168 = 15/168.
So (15/168) x = 10, hence x = 10 × (168/15) = 112 km.
Total distance = 2x = 2 × 112 = 224 km.
Answer: 224 km.