If he rows 1 mile upstream and then floats back to the starting place, how many minutes will be required for the roundtrip?
2007-05-18 04:37:24 · 6 answers · asked by Lizzy B 1 in Science & Mathematics ➔ Mathematics
Going upstream his effective rate is 2 miles per hour. One mile will take him 30 minutes which is half an hour.
Floating downstream his rate is 3 miles per hour. One mile will take him 20 minutes which is one-third of an hour.
Total travel time: 30 + 20 = 50 minutes
2007-05-18 04:42:09 · answer #1 · answered by ecolink 7 · 0⤊ 0⤋
Upstream net speed = 2 mph
t (upstream) = 1 / 2 h
t (downstream) = 1 / 3 h
Total time = 5 / 6 hours = 50 mins.
2007-05-18 04:55:44 · answer #2 · answered by Como 7 · 0⤊ 0⤋
On the trip upstream his speed relative to the shore whould be 2 miles per hour, downstream it would be 3.
It would take 1/2 an hour to go up and 1/3 an hour to go down.
5/6 of an hour total
2007-05-18 04:42:37 · answer #3 · answered by Blank 2 · 0⤊ 0⤋
His net movement up stream is 2 mph. It would take him half an hour at this pace to row 1 mile. Floating back 1 mile at 3 mph would take him 20 min. so his total time in the water is 50 minutes from start to...start.
2007-05-18 04:43:57 · answer #4 · answered by Ray J 1 · 0⤊ 0⤋
Avg speed = 3/(3/2) = 2 mph = speed of boat in nevertheless water - speed of modern speed of boat in nevertheless water = 4 mph go back vacation speed = speed of boat in nevertheless water + speed of modern = 4 + 2 = 6 mph Time taken = 3/6 = 0.5 hours EDIT: Sorry made a mistake in this this morning.
2016-11-04 08:23:50 · answer #5 · answered by nocera 4 · 0⤊ 0⤋
yep 50 I agree
2007-05-18 04:48:10 · answer #6 · answered by Leonidas 4 · 0⤊ 0⤋