How much sparkling water would you need to mix with 9 quarts of grape juice

You are at a restaurant and owe $38 for your meal. you want to leave a 20% tip. how much will your tip be?

The price of a visit to the dentist is calculated according to the formula 50+100n50+100n where nn is the number of cavities the dentist finds. on your last visit to the dentist, 22 cavities were found. what was the cost of your visit?

Janie has $3. she earns $1.20 for each chore she does and can do fractions of chores. she wants to earn enough money to buy a cd for $13.50.