Question:

The number of days required by three persons A, B, C independently to complete a given work is as per the ratio \(3:4:6\). How many days are required for B and C together to complete the work? Statements: (I) A is \(100\%\) more efficient than C. (II) C requires 27 days more than A to complete the work.

Show Hint

In time and work problems, ratios only give relative values. To find exact time, always determine the multiplying factor.
Updated On: Jul 15, 2026
  • Statement (I) alone is sufficient to answer the question, but (II) alone is not sufficient.
  • Statement (II) alone is sufficient to answer the question, but (I) alone is not sufficient.
  • Both the statements (I) and (II) are sufficient to answer the question, but neither statement alone is sufficient.
  • Both the statements (I) and (II) together are not sufficient to answer the question and additional data are required.
Show Solution
collegedunia
Verified By Collegedunia

The Correct Option is B

Solution and Explanation

Concept: Time taken to complete work is inversely proportional to efficiency. If the ratio of days taken by A, B, and C is: \[ 3:4:6 \] then let their times be: \[ 3x,\;4x,\;6x \] To find the exact number of days for B and C together, we first need the value of \(x\).

Step 1:
Checking Statement (I).
Given: A is \(100\%\) more efficient than C. This means: \[ E_A=2E_C \] Since time is inversely proportional to efficiency: \[ T_A=\frac{T_C}{2} \] This only confirms: \[ 3x=\frac{6x}{2} \] which is already consistent with the given ratio. No actual value of \(x\) is obtained. So, Statement (I) alone is not sufficient.

Step 2:
Checking Statement (II).
Given: C requires 27 days more than A. From ratio: \[ T_C-T_A=27 \] \[ 6x-3x=27 \] \[ 3x=27 \] \[ x=9 \] Thus, \[ T_B=4x=36 \] \[ T_C=6x=54 \] Now combined work rate: \[ \frac{1}{36}+\frac{1}{54} \] Taking LCM \(108\): \[ =\frac{3+2}{108} \] \[ =\frac{5}{108} \] So total time: \[ =\frac{108}{5} \] \[ =21.6 \text{ days} \] Thus, Statement (II) alone is sufficient. Hence, the correct answer is (B).
Was this answer helpful?
0
0