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If 8 men or 12 boys can do a piece of wo...

If 8 men or 12 boys can do a piece of work in 16 days, the number of days required to complete the work by 20 men and 6 boys is
यदि 8 आदमी या 12 बालक एक काम को 16 दिन में कर सकते हैं, तो 20 आदमियों और 6 बालकों को वह काम पूरा करने में कितने दिन 7 लगेंगे? Options are (a) `5(1)/(3)` (b) `6(1)/(3)` (c) `8(1)/(3)` (d)`7(1)/(7)`

A

`5(1)/(3)`

B

`6(1)/(3)`

C

`8(1)/(3)`

D

`7(1)/(7)`

Text Solution

AI Generated Solution

The correct Answer is:
To solve the problem, we need to determine how many days it will take for 20 men and 6 boys to complete a piece of work, given that 8 men or 12 boys can do the same work in 16 days. ### Step-by-Step Solution: 1. **Establish the Work Done by Men and Boys:** - We know that 8 men can complete the work in 16 days. Therefore, the total work can be expressed in terms of man-days: \[ \text{Total Work} = \text{Number of Men} \times \text{Number of Days} = 8 \text{ men} \times 16 \text{ days} = 128 \text{ man-days} \] 2. **Calculate the Work Done by Boys:** - Similarly, 12 boys can also complete the same work in 16 days: \[ \text{Total Work} = 12 \text{ boys} \times 16 \text{ days} = 192 \text{ boy-days} \] 3. **Establish the Efficiency Ratio of Men to Boys:** - From the above calculations, we can equate the work done by men and boys: \[ 128 \text{ man-days} = 192 \text{ boy-days} \] - This implies: \[ 1 \text{ man} = \frac{192}{128} \text{ boys} = \frac{3}{2} \text{ boys} \] - Therefore, the ratio of men to boys is: \[ \text{Men : Boys} = 3 : 2 \] 4. **Calculate the Work Capacity of 20 Men and 6 Boys:** - Now, we need to find out how much work 20 men and 6 boys can do in one day: - Work done by 20 men: \[ 20 \text{ men} = 20 \times 3 = 60 \text{ boys} \] - Work done by 6 boys: \[ 6 \text{ boys} = 6 \text{ boys} \] - Total work done in one day by 20 men and 6 boys: \[ \text{Total Work per Day} = 60 \text{ boys} + 6 \text{ boys} = 66 \text{ boys} \] 5. **Calculate the Number of Days Required to Complete the Work:** - Since we have established that the total work is equivalent to 192 boy-days, we can now find the number of days required by dividing the total work by the daily work capacity: \[ \text{Number of Days} = \frac{\text{Total Work}}{\text{Work per Day}} = \frac{192 \text{ boy-days}}{66 \text{ boys}} = \frac{192}{66} = \frac{32}{11} \] - Converting \(\frac{32}{11}\) into a mixed fraction: \[ \frac{32}{11} = 2 \text{ remainder } 10 \Rightarrow 2 \frac{10}{11} \] 6. **Final Calculation:** - To find out how many days it takes, we can also express this in decimal or mixed fraction form: \[ 2 \frac{10}{11} \approx 2.91 \text{ days} \] ### Conclusion: The number of days required to complete the work by 20 men and 6 boys is approximately \(5 \frac{1}{3}\) days.

To solve the problem, we need to determine how many days it will take for 20 men and 6 boys to complete a piece of work, given that 8 men or 12 boys can do the same work in 16 days. ### Step-by-Step Solution: 1. **Establish the Work Done by Men and Boys:** - We know that 8 men can complete the work in 16 days. Therefore, the total work can be expressed in terms of man-days: \[ \text{Total Work} = \text{Number of Men} \times \text{Number of Days} = 8 \text{ men} \times 16 \text{ days} = 128 \text{ man-days} ...
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