Rajesh can finish 1/5 of his home work in one hour. Seema can finish 3/7 of…

2023

Rajesh can finish 1/5 of his home work in one hour. Seema can finish 3/7 of her homework in 90 minutes and Ramya can finish 3/4 of her homework in three and a half hours . If all of them start their home work at 12.00 PM and can go to play as soon as they all finish their homework. When can they start to play , if they take a break at 3.30 PM for 30 minutes?

  1. A.

    5:30 pm

  2. B.

    4:50 pm

  3. C.

    4:30 pm

  4. D.

    5:10 pm

Attempted by 10 students.

Show answer & explanation

Correct answer: A

Step 1: Find each person’s total time to finish homework.

  • Rajesh: He does 1/5 in 1 hour, so the whole work takes 5 × 1 hour = 5 hours = 300 minutes.

  • Seema: She does 3/7 in 90 minutes, so whole work = 90 × (7/3) = 210 minutes.

  • Ramya: She does 3/4 in 3.5 hours, so whole work = 3.5 × (4/3) = 14/3 hours = 4 2/3 hours = 280 minutes.

Step 2: Determine work done before the break.

  • They start at 12:00 PM and take a break at 3:30 PM, so they work 3.5 hours = 210 minutes before the break.

Step 3: Compute remaining time for each after the break.

  • Rajesh: 300 − 210 = 90 minutes remaining → resumes at 4:00 PM and finishes at 5:30 PM.

  • Seema: 210 − 210 = 0 minutes remaining → already finished at 3:30 PM.

  • Ramya: 280 − 210 = 70 minutes remaining → resumes at 4:00 PM and finishes at 5:10 PM.

Final conclusion: They can start to play at 5:30 PM.

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