Posted by **carl** on Wednesday, August 17, 2011 at 12:48am.

A boat can travel 114 miles upstream

in the same time that it can travel 186 miles downstream.

If the speed of the current is 6 miles per hour,

find the speed of the boat without a current.

- algebra -
**carl**, Wednesday, August 17, 2011 at 3:10pm
any help would be greatly appreciated :)

- algebra -
**Henry**, Wednesday, August 17, 2011 at 4:19pm
Speed of boat in still water = V mi/h.

Speed of boat upstream = V-6 mi/h.

Speed of boat down stream = V+6 mi/h.

(V-6)t = 114 mi.

Eq1: Vt - 6t = 114.

(V+6)t = 186 mi.

Eq2: Vt + 6t = 186.

Add Eq1 and Eq2 and get:

2Vt = 300,

Vt = 150.

In Eq1, substitute 150 for Vt:

150 - 6t = 114,

-6t = 114 - 150 = -36,

t = 6h.

In Eq2, substitute 6 for t:

6V + 6*6 = 186,

6V + 36 = 186,

6V = 150,

V = 25mi/h.

## Answer This Question

## Related Questions

- math - River Current A boat can travel 36 miles upstream in the same time that ...
- Algebra - A boat can travel upstream 14 miles in same it can travel downstream 8...
- algebra - 36 Upstream, downstream. Junior’s boat will go 15 miles per hour in ...
- algebra - Show a complete solution. Upstream, downstream. Junior’s boat will go ...
- Intermediate Algebra - in still water, a paddle boat averages 10 miles per hour...
- algebra - A boat travel 4 miles upstream with a current of 5 miles per hour. It ...
- Intermediate Algebra Word Problem - A river's current is 4mph. A boat travels 48...
- Math - A boat, which moves at 18 mph in still water, travels 14 miles downstream...
- Algebra - The current of a river moves at 3 miles per hour. It takes a boat 3 ...
- Math - Steve's boat will go 14 miles per hour in still water. If he can go 13 ...

More Related Questions