A package states that there are 60 calories in 12 crackers and 75 calories in 15 crackers. Since the relationship is proportional, how many calories are there in 180 crackers?

There are 900 calories in 180 crackers. Write 60 calories for 12 crackers as 60/12. Then make x/180, showing that there are 180 crackers with an unknown amount of calories. Cross multiply 60 and 180, which is 10,800. Divide 10,800 by 12, and you get 900.