wikiHow Proportions Practice Problems 1. If x is to 8 as 10 is to 40, what is the value of x? 2. If 2 is to x as 10 is to 50, what is the value of x? 3. If 4 is to 8 as x is to 12, what is the value of x? 4. If 3 is to 4 as 6 is to x, what is the value of x? 5. If 2 is to 5 as 10 is to x, what is the value of x? 6. If 15 is to x as 30 is to 45, what is the value of x? 7. If 12 is to x as 36 is to 48, what is the value of x? 8. If 5 is to 6 as x is to 24, what is the value of x? 9. If 9 is to 15 as x is to 40, what is the value of x? 10. If 1 is to 3 as x is to 9, what is the value of x? 11. A recipe calls for 2 cups of flour for every 3 cups of water. How much flour is needed for 9 cups of water? 12. A contractor can finish a project in 5 days with 10 workers. How many workers are needed to finish the project in 3 days? 13. A car rental charges $20 per day for 3 days or $50 for 7 days. Which option is cheaper per day? 14. A coffee shop has a mix of regular and decaf coffee. If the mix is 1 part decaf to 4 parts regular, how many parts of regular coffee are in a 20-part mixture? 15. A pool is being filled with water from two hoses. If the first hose fills the pool in 6 hours and the second hose fills the pool in 4 hours, how long will it take to fill the pool using both hoses together? 16. A company sells 1,000 widgets for $5 each or 2,000 widgets for $8 each. Which option generates more revenue? 17. A shirt is on sale for 20% off its original price of $40. What is the sale price? 18. A truck can travel 480 miles on 20 gallons of gasoline. How many miles can it travel on 30 gallons of gasoline? 19. If a worker earns $25 for 4 hours of work, how much will the worker earn for 6 hours of work? 20. A map has a scale of 1 inch equals 50 miles. If the distance between two cities on the map is 2.5 inches, what is the actual distance between the cities? Page