Multiple choice

A can do 25% of the work in 8 days, B can 1/8th of the work in 12 days. In how many days they can do 75% of the job by working together?

  1. 24

  2. 9

  3. 21

  4. 18

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

A does 25% (1/4) work in 8 days, so A's rate = 1/32 per day. B does 1/8 work in 12 days, so B's rate = 1/96 per day. Combined rate = 1/32 + 1/96 = 4/96 = 1/24 per day. For full work: 24 days. For 75% (3/4) of work: 3/4 × 24 = 18 days. Options A, B, C are incorrect conversions between percentages and fractions.