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A, B and C can do a piece of work individually in 8, 12 and 15 days respectively. A and B start working together but A quits alter working for 2 days. After this, C joins and works till completion of the work. In how many days will the work be completed?

A) \( 3\)\( \Large \frac{8}{9} \)
B) \( 5\)\( \Large \frac{8}{9} \)
C) \( 5\)\( \Large \frac{2}{3} \)
D) \( 6\)\( \Large \frac{1}{18} \)

Correct Answer:

A) \( 3\)\( \Large \frac{8}{9} \)

Description for Correct answer:

Total work done by A and B in 2 days = 50 unit

Hence total work left are 2 days = 120 50 = 70 unit

Now C joins with B,

1 day work of (B + C)= 18 unit

70 unit of remaining work will be completed in \( \Large \frac{78}{10} \) day = \( \Large \frac{35}{9} \) day = \( \Large 3 \frac{8}{9} \) day

Hence total number of days = \( \Large 2 + 3 \frac{8}{9} \) = \( \Large 5 \frac{8}{9} \) days

Option (A)is correct

Part of solved CDS Maths(1) questions and answers : Exams >> CDSE >> CDS Maths(1)

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