Homework Help: Maths

Posted by Maybel on Tuesday, August 19, 2008 at 4:34am.

Tom was floating down the river on a raft when, 1km down, Michael took to the water in a rowing boat. Michael rowed downstream at his fastest pace. Then he turned around and rowed back, arriving at his starting point just when Tom drifted by.

If Michael's rowing speed in still water is ten times the speed of the current in the river, what distance had Michael covered before he turned his boat around?

Maths - drwls, Tuesday, August 19, 2008 at 7:27am
Where was Tom when Michael started rowing? He must have been farther upstream at the time. I will assume Tom was one km upstream when Michael started rowing.
Let v = the river speed and V = 10v be Michael's speed in still water.
Michael rows downstream at a land speed v + V = 11 v and upstream at a land speed of V-v = 9 v. Tom travels at speed v (by floating)

Let T be the time they both are on the water between when Michael starts and finishes rowing.

Let t be the time Micheal rows downstream; T-t is the time he rows upstream

v T = 1 km

11 v t = 9 v (T-t)= 9 - 9 vt
20 vt = 9
vt = 0.45 km

So Tom floated 0.45 km while Micheal rowed downstream and 0.55 km while he rowed upstream. Since Micheal rowed downstream 11 times faster than Tom floated, he would have travelled 11*0.45 = 4.95 km in that time
Maths - Anonymous, Thursday, June 9, 2011 at 3:17pm
dfh

Answer this Question

Related Questions

8th Grade Math - Tom was floating down the river on a raft when, 1km lower down...
math - A boat's crew rowed 12 miles downstream, with the current, in 1.5 ...
Math - A boat crew rowed 20 miles downstream, with the current, covered the same...
algebra - A boat's crew rowed 13.5 miles downstream, with the current, in 1....
Physics - A boat travelling at 30km/h relative to water is headed away from the ...
Physics - A boat travelling at 30km/h relative to water is headed away from the ...
Algebra - What system of equations do I use to solve the following question? A ...
Math - A boat crew rowed 20 miles downstream, with the current, in 2hours. The ...
Physics - A boat sets off perpendicular to the bank, to cross a river width of ...
Physics - A boat travelling at 30km/hr relative to water is headed away from the...

For Further Reading

First Name:
School Subject:
Answer: