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Question

Raj is 60% more efficient than Sundar and Sundar can finish a certain task in 16 days. How many days will Raj alone take to complete the same task?

This question was previously asked in
RRB NTPC 2019 CBT 1 Question Paper (8-Mar-2021) (Shift 2)
The correct answer is
10

Efficiency Comparison

Raj is 60% more efficient than Sundar. This means Raj's work rate is higher.

If Sundar's efficiency is represented as 100%, Raj's efficiency is:

$100\% + 60\% = 160\%$ of Sundar's efficiency.

Efficiency Ratio

The ratio of their efficiencies is:

$\text{Efficiency}_{\text{Raj}} : \text{Efficiency}_{\text{Sundar}} = 160 : 100 = 8 : 5$.

Time Calculation Based on Efficiency

Work and time are inversely related. Higher efficiency means less time is needed.

The ratio of time taken is the inverse of the efficiency ratio:

$\text{Time}_{\text{Raj}} : \text{Time}_{\text{Sundar}} = 5 : 8$.

Given Sundar takes $T_{Sundar}$ = 16 days.

Let Raj take $T_{Raj}$ days. The relationship is:

$\frac{T_{Raj}}{T_{Sundar}} = \frac{5}{8}$

Substituting Sundar's time:

$\frac{T_{Raj}}{16} = \frac{5}{8}$

Solving for $T_{Raj}$:

$T_{Raj}$ $= 16 \times \frac{5}{8}$

$T_{Raj}$ $= 10$ days.

Result: Raj's Task Time

Therefore, Raj will alone take 10 days to complete the same task.

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Similar Questions

  1. A can do $\frac{1}{5}^{\text{th}}$ of some work in 12 days, B can do $20\%$ of the same work in 10 days, C can do $\frac{1}{6}^{\text{th}}$ of the work in 8 days and D can do $\frac{1}{5}^{\text{th}}$ of the work in 12 days. Who will complete the work first if all four started to work at the same time?
  2. A can do a certain work in 45 days. B is 50% more efficient than A, and C is 3 times as fast as A. They started the work together but C left 7 days before completion of the work. In how many days was the entire work completed?
  3. Manoj is twice as efficient a fisherman as Anuraj, and together they complete a piece of work in 22 days. In how many days can Anuraj alone complete the same work?

  4. Five women can do a work in thirty six days. If the ratio between the capacity of a man and a woman is 3:1, then find how many days it will take 5 men to complete the same work?
  5. If 15 persons can do a job in 30 days, then 30 persons with twice the efficiency can do the same job in how many days?
  6. Raju is thrice as good as a workman as Vinod and together they can finish a task in 21 days. In how many days can Vinod alone complete the work?
  7. If Raju is thrice as good workman as Ravi and takes 20 days less than him to complete a piece of work, then find the time taken by Ravi to complete the work.
  8. John is only 40% as efficient as Jesse. If John alone can do a piece of work in 35 days, how many days will it take the duo to complete the work, if they work together?
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Important Questions from Work Efficiency

  1. Sumi can complete a job working 5 hours per day in 2 days. If she doubles her working hours per day, then in how many days will she complete the work?

  2. Five men and 2 boys can do in 30 days as much work as 7 men and 10 boys can do in 15 days. How many boys should join 40 men to do the same work in 4 days?

  3. A man completes 7/8 of a job in 21 days. How many more days will it take him to finish the job if quantum of work further increased by 50%?

  4. 24 men and 12 women can do a piece of work in 30 days. In how many days can 12 men and 24 women do the same piece of work?

  5. 3 men working 7 hours a day can complete a piece of work in 45 days. In how many days will 9 men working 6 hours a day complete the same work?

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