Answer:
750 sheets
Explanation:
2.5 kilograms=2.5*1000=2500 grams
2500/40=62.5 stacks-of-12-papers
62.5*12=750 sheets of paper
To check our work:
Let's set x as the weight of one sheet of paper.
12x=40 grams, x= 3 1/3 (three and one thirds) grams
3 and 1/3 *750= 2500 grams
2500 grams=2.5 kilograms