In a class of 30 students, if 12 are girls, the ratio of girls to boys is ______.

If a dress originally priced at $80 is on sale for 25% off, the discount amount is ______ dollars.

A recipe requires a ratio of water to flour of 3:5. If you have 15 cups of flour, you need ______ cups of water.

If a store sells an item for $120 after applying a 20% discount, the original price was ______ dollars.

In a survey, 40% of respondents said they preferred cats over dogs. If 200 people were surveyed, ______ respondents preferred cats.

If two numbers are in the ratio 4:3 and their sum is 28, the larger number is ______.

If you divide a number by 7 and then add 11, you get 25. The original number is ______.

A car travels 150 miles using 5 gallons of fuel. The car's fuel efficiency is ______ miles per gallon.

If a population of bacteria doubles every hour and starts at 500, it will be ______ after 3 hours.

If a student scores 45 out of 60 on a test, the percentage score is ______%.