- A70 min
- B84 min
- C120 min
- D168 min
Step-by-Step Solution
Pumps 1 and 3: L/min; min. (120 min is pump 1 alone; 84 min is pump 2.)
Answer: A) 70 min
The table gives the litres per minute that each of three pumps can lift. Pumps 1 and 3 are run together to fill a 4,200-litre tank. How long does it take?
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