- A72 min
- B120 min
- C90 min
- D45 min
Step-by-Step Solution
Together L/min; min. (72 min is B alone; 90 min uses the average flow 40 L/min.)
Answer: D) 45 min
An overhead tank holds 3,600 litres. Pipe A delivers 30 litres per minute and pipe B delivers 50 litres per minute. With both running, how long does the empty tank take to fill?
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