Multiple choice

A and B working together can do a piece of work in 6 days. If A works alone in the beginning for 2 days and completes 25% of the job, how many days B will take to complete the rest of the work?

  1. 24 days

  2. 36 days

  3. 18 days

  4. 9 days

Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

A and B together take 6 days, so their combined rate is 1/6 work per day. A works 2 days and completes 25% (1/4) of the job, so A's rate is (1/4)÷2 = 1/8 work per day. B's rate = 1/6 - 1/8 = 1/24 work per day. Remaining work = 3/4. Time for B = (3/4)÷(1/24) = 18 days.