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CAN I GET SOME HELP OVER HERE? Ina Crespo rowed 12 miles down the Habashabee River in 2 ​hours, but the return trip took her 3 hours. Find the rate Ina rows in still water and the rate of the current. Let x represent the rate Ina can row in still water and let y represent the rate of the current. Ina can row ? mph in still water

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Answer: The speed of Ina in still water is 5mph

Explanation:

If the speed of Ina on still water is x, and the speed of the river is y:

The total speed of Ina when she goes along with the current is:

S = x + y

when she goes against the current we have:

St = x - y.

Now we can use the relation:

speed = time/velocity.

along with the current, we have:

x + y = 12mi/2h = 6mi/h

against the current we have:

x - y = 12mi/3h = 4mi/h

So we have the equations

x + y = 6mi/h

x - y = 4mi/h

in the first equation we can isolate x

x = 6mi/h - y

now we replace this in the second equation:

(6mi/h - y) - y = 4mi/h

6mi/h - 2y = 4mi/h

-2*y = 4mi/h - 6mi/h = -2mi/h

y = 1mi/h

now we replace this in the first equation:

x + 1mi/h = 6mi/h

x = 5mi/h.

The speed of Ina in still water is 5mph

User Dion Segijn
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