Answer:
A 12 pound baby is equivalent to 5.4kg, while a watermelon weighs 7.5kg, which is obviously larger than 5.4, so the watermelon weights more.
Explanation:
To start off, we should convert the numbers in the same units. The question has told us that 1 pound is around 0.45kg. So let's do 12 * 0.45 which gives us 5.4kg. We already know that a watermelon weighs 7.5 kilograms, so from this we know that the watermelon weighs more.