Jack has a 3 litre jug of water. What is the maximum number of 0.5 litre bottles that he can completely fill?
(A) 3
(B) 1.5
(C) 6
(D) 12
(E) 15
Using a 1 litre jug of water, Jack could fill two 0.5 (one half) litre bottles of water.

Using a 3 litre jug of water, Jack could fill $3 \times 2=6$ bottles of water.

(Check: $3 \div 0.5=3 \div \frac{1}{2}=3 \times 2=6$ )

ANSWER: (C)