Multiple choice

Prahlad has done 1/3rd of a job in 30 days, Sarfaraz completes the rest of the job in 90 days. In how many days can they together do the job?

  1. 27 days

  2. 18 days

  3. 54 days

  4. 36 days
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Prahlad does 1/3 in 30 days, so he does the whole job in 90 days. Sarfaraz does the remaining 2/3 in 90 days, so he does the whole job in 135 days. Together, their rate is 1/90 + 1/135 = (3+2)/270 = 5/270 = 1/54. They take 54 days.

AI explanation

Prahlad finishes 1/3 of the job in 30 days, meaning his rate is 1/90 of the job per day. Sarfaraz finishes the remaining 2/3 of the job in 90 days, giving him a rate of 2/270, or 1/135 of the job per day. Their combined daily work is 1/90 + 1/135 = 5/270, which simplifies to 1/54. Therefore, working together, they complete the entire job in 54 days.

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