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Question
6 men can complete the electric fitting in a building in 7 days. How many days will it take if 21 men do the job?
Solution
\[\text{ It is given that 6 men can complete a job in 7 days } . \]
\[ \therefore \text{ Time taken by 1 man to complete the same job } = \left( 6 \times 7 \right) = 42 \text{ days } \]
\[ \therefore \text{ Time taken by 21 men to complete the same job } = \frac{42}{21} = 2 \text { days } \]
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