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algebra ia

 
 
TAmy的头像
algebra ia
TAmy - 2019年07月26日 Friday 05:50
 
Water flows in a river at 3 m/s. Traveling upstream, George's speed boat is able to travel 1.8 km in 3 minutes. How many m/s can George's boat travel in still water? 

It takes a pigeon 2 hours to fly with the wind between two houses, and 3 hours against the wind. If the wind blows at a speed of 2.5 miles per hour, at what speed in mph would the pigeon travel in a windless day?

 
ReynosoDavid的头像
Re: algebra ia
ReynosoDavid - 2019年07月31日 Wednesday 22:37
 
For the first problem remember that, since George is travelling upstream, the speed of his boat is equal to the speed of the river plus the speed of his boat in still water.


For the second problem, the speed behaves similarly as in the first problem. When the pigeon travels in the same direction as the wind its speed is equal to the speed of the wind plus its real speed; and when it travels in the opposite direction of the wind its speed is equal to its real speed minus the speed of the wind.

 
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