Four dwarfs would prepare firewood for Snow White in580 minutes. After an hour and a half they recruit friends so that finished preparing the wood for 280 minutes. How many dwarfs they recruited?

Correct answer:

x =  3

Step-by-step explanation:

1.5•60•4 + 280•(x+4) = 580•4

280x = 840

x = 3

Our simple equation calculator calculates it.

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