No.134 Uphill and Downhill
Example
A person made a round trip from Town A to Town B over a mountain pass. The uphill speed was 3 km/h and the downhill speed was 6 km/h. The outward trip took 3 hours and the return trip took 2 hours 30 minutes. Find the distance from Town A to the pass and from the pass to Town B.
POINT
On the return trip, the uphill and downhill sections are reversed. Express the time for each section as distance divided by speed.
7 km from Town A to the pass; 4 km from the pass to Town B
TRY
TRY 1
The uphill speed is 2 km/h and the downhill speed is 4 km/h. The outward trip took 4 hours and the return trip took 3 hours 30 minutes. Find the distances from A to the pass and from the pass to B.
A to pass: 6 km; pass to B: 4 km
TRY 2
The uphill speed is 3 km/h and the downhill speed is 6 km/h. The outward trip took 2 hours 30 minutes and the return trip took 2 hours. Find the distances from A to the pass and from the pass to B.
A to pass: 6 km; pass to B: 3 km