Two persons A and B complete a task in 15 days, when they work together.…
2023
Two persons A and B complete a task in 15 days, when they work together. Person A completes the task in 20 days if he works alone. How many days will B take to finish the task alone?
Answer: C. 60 days — Step 1: Let the total work be 1 unit. When A and B work together, they complete the work in 15 days. So, their combined work rate is 1/15 per day. Step 2: A…
- A.
35 days
- B.
25 days
- C.
60 days
- D.
More than one of the above
- E.
None of the above
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Correct answer: C
Step 1: Let the total work be 1 unit. When A and B work together, they complete the work in 15 days. So, their combined work rate is 1/15 per day.
Step 2: A alone completes the work in 20 days. So, A's work rate is 1/20 per day.
Step 3: B's work rate = Combined rate - A's rate = 1/15 - 1/20.
Step 4: Calculate 1/15 - 1/20 = (4 - 3)/60 = 1/60. So, B's rate is 1/60 per day.
Step 5: Therefore, B alone will take 60 days to complete the work.
हिन्दी उत्तर:
चरण 1: कुल कार्य 1 इकाई मानें। A और B मिलकर 15 दिन में कार्य पूरा करते हैं। इसलिए, उनकी संयुक्त कार्य दर 1/15 प्रति दिन है।
चरण 2: A अकेले 20 दिन में कार्य पूरा करता है। इसलिए, A की कार्य दर 1/20 प्रति दिन है।
चरण 3: B की कार्य दर = संयुक्त दर - A की दर = 1/15 - 1/20।
चरण 4: 1/15 - 1/20 = (4 - 3)/60 = 1/60। इसलिए, B की दर 1/60 प्रति दिन है।
चरण 5: अतः, B अकेले कार्य पूरा करने में 60 दिन लेगा।
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