CSAT: Quantitative Aptitude Time & Work Quiz

Question

Surya can complete a work in 10 days, Gopi can complete it in 15 days, Praveen can complete it in 20 days, and Dhanush Kodi can complete it in 30 days. If all four work together, how many days will it take to finish the work?

Accepted Answer

Surya can complete the work in 10 days, so he does 1/10 of the work per day. Gopi can complete it in 15 days, so he does 1/15 of the work per day. Praveen can complete it in 20 days, so he does 1/20 of the work per day. Dhanush Kodi can complete it in 30 days, so he does 1/30 of the work per day. Together, their daily work is: 1/10 + 1/15 + 1/20 + 1/30 Finding the LCM of 10, 15, 20, 30 = 60: 1/10 = 6/60 1/15 = 4/60 1/20 = 3/60 1/30 = 2/60 Adding them: 6/60 + 4/60 + 3/60 + 2/60 = 15/60 = 1/4 So together, they complete 1/4 of the work in one day. To finish the full work: 1 ÷ (1/4) = 4 days Answer: 4 days (Option B)

Answer

5 days

Answer

4 days

Answer

3.75 days

Answer

3.5 days

Options

Explanation

Step 1: Work done by each per day

Step 2: Total work done by all four in 1 day

Step 3: Total days to complete the work

✅ Answer

Question