if the exchange rate is 2 brazilian reals per dollar and a meal in rio costs 20 reals, then how many dollars does it take to buy a meal in rio?

Arestaurant offers a $12 dinner special that has 5 choices for an appetizer, 12 choices for an entrée, and 4 choices for a dessert. how many different meals are available when you select an appetizer, an entrée, and a dessert? a meal can be chosen in nothing ways. (type a whole number.)

The constant of proportionality is always the where k is the constant of proportionality. additionally, you can find the constant of proportionality by finding the ratio for any point onasap

Icould really use some with this question.