# Tractors

Fields go plow two tractors with various performance. The first tractor plow whole field in 11 hours, the second tractor plow whole field 19 hours longer.

How long take plow whole field with two tractors?

Result

t =  8.049 h

#### Solution:

t*(1/11 + 1/30) = 1

41t = 330

t = 33041 ≈ 8.04878

Calculated by our simple equation calculator.

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