Answer: he would need either 6 cups whose volume is 1/2 litres per cuo or
he would need 12 cups whose volume is 1/4 litres per cup
Explanation:
Total amount of water required to fill the jug is 3 litres. He has measuring cups of 1/2 and 1/4 litres only.
If he decides to fill the jug with only the 1/2 litres cup, the number of 1/2 litres cups that he would need is
3/(1/2) = 3/0.5 = 6
If he decides to fill the jug with only the 1/4 litres cup, the number of 1/4 litres cups that he would need is
3/(1/4) = 3/0.25 = 12