Question 1137025
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The response from tutor @ikleyn shows one good way of solving the problem using logical reasoning and some simple arithmetic.<br>
Here is another similar way to solve the problem.<br>
Since A works twice as fast as B, when they work together A does 2/3 of the job.<br>
Then, since together the two of them take 2 days to paint the house, the time required by A alone would be 2*(3/2) = 3 days.<br>
And so then the time required by B alone would be twice that, or 6 days.