- AA alone, ₹240
- BBoth together, ₹180
- CB alone, ₹180
- DBoth together, ₹216
Step-by-Step Solution
A alone: . B alone: . Together: h at ₹90/h . Cheapest: B alone, ₹180.
Answer: C) B alone, ₹180
Which is the cheapest way to fill an empty tank: pump A alone (fills it in 4 hours, power ₹ 60 per hour), pump B alone (fills it in 6 hours, ₹ 30 per hour), or both together?
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