Jock decided to swim 10 km up Bega river without leaving the river. He swam 2 km every hour then floated on his back for 10 minutes. Each time he floated, the current dragged him back 1 km. How long did it take Jock to complete the swim?

Question

.sam. · Answer

Do you have the answer?

anonymous · Answer

it took him 3hours and 20 minutes

.sam. · Answer

d=10km
v=2km/h = 1/30 km/min
time required=300 min, which is 5hours
5hours =50minutes backwards,
5km backwards=additional 150mins
300+150=450mins or 7.5hours

.sam. · Answer

You check the answer.

.sam. · Answer

Because from the additional 150mins , I'm not sure whether he will move backwards again.

anonymous · Answer

thanx