a boat going upstream at 4 mph then travels downstream at 10 mph. what is the rate of the boat in still water

Mathematics

1 answer:

elixir [45]3 years ago

7 0

Answer:

7 mph

Step-by-step explanation:

If b is the rate of the boat, and s is the rate of the stream, then:

b − s = 4

b + s = 10

Solve the system of equations with substitution or elimination. Using elimination, add the equations together:

2b = 14

b = 7

The boat's rate is 7 mph.

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The perimeter of a playing card is 30 centimeters. The area is 50 square centimeters. What are the dimensions of the playing car

Arlecino [84]

Step-by-step explanation:

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