Q. 15 men take 20 days to complete a job working 8 hours a day. The number of hours a day should 20 men take to complete the job in 12 days :
Answer: 10 hours
Notes: $latex M_{1}D_{1}T_{1} = M_{2}D_{2}T_{2}$ $latex => 15\times 20\times 8 = 20\times 12\times T_{2}$ $latex => T_{2} = \frac{15\times 20\times 8}{20\times 12} = 10\ hours&s=1$ Hence option [B] is correct answer.<

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