To compare these two quantities, we need to convert one of them so that they are both in the same units.
1 kilogram is equal to 1000 grams.
Therefore, 9 kilograms can be converted to grams as:
9 kilograms = 9 x 1000 grams = 9000 grams
Now we can compare the two quantities:
7500 grams < 9000 grams
Therefore, 9 kilograms (which is equivalent to 9000 grams) is heavier than 7500 grams.