1. The ratio of salt to water in a solution is $3:20$. How many ounces of salt are needed for 5 quarts of water? (1 quart = 32 fluid ounces)
2. A recipe calls for a ratio of $2:5$ for oil to vinegar. If a chef uses $20$ tablespoons of vinegar, how many tablespoons of oil are needed to keep the same ratio?
3. In a class, the ratio of students wearing sneakers to students not wearing sneakers is $9:7$. If $63$ students are wearing sneakers, how many students are not wearing sneakers?
4. The sum of 3 positive integers is 120 and their ratio is $1:2:3$. What is the value of the largest integer?
5. If the ratio of cats to dogs at a shelter is $4:5$ and there are $30$ dogs, how many cats are there?
6. Which ratio is equivalent to $6:9$?
7. If the ratio of cats to dogs in a shelter is 4:3, how many cats are there when there are 21 dogs?
8. If a scale model uses a scale of 1:50 and the model measures 2 meters, what is the actual length?
9. What is the value of $x$ in the proportion $\frac{5}{x} = \frac{10}{15}$?
10. What is the scale factor from a rectangle with dimensions 4 cm by 8 cm to one with dimensions 16 cm by 32 cm?
11. If the ratio of apples to oranges is 2:3 and there are 12 oranges, how many apples are there?
12. What is the value of $x$ in the proportion $\frac{11}{x}=\frac{22}{18}$? (If $\frac{a}{b}=\frac{c}{d}$, then $ad=bc$.)
13. A bag of trail mix is made with nuts and dried fruit in a ratio of $3:2$. If the bag contains 25 ounces total, how many ounces of nuts are in the bag?
14. If the ratio of boys to girls in a club is $3:4$ and there are 28 girls, how many boys are in the club?
15. A classroom has a ratio of students wearing sneakers to students not wearing sneakers of $7:3$. If 21 students are wearing sneakers, how many students are not wearing sneakers?
16. Which ratio is equivalent to $6:11$?
17. A map uses a scale of $1$ inch to $4$ miles. If two towns are $7.5$ inches apart on the map, what is the actual distance between the towns in miles?
18. If the ratio of red to blue marbles is 3:4 and there are 36 blue marbles, how many red marbles are there?
19. A model car is built at a scale of $1:18$ (model:real). If the real car is $162$ inches long, how long is the model car in inches?
20. A bag contains only red and green marbles in the ratio $5:3$ (red:green). If there are $64$ marbles in total, how many red marbles are in the bag?
21. What is the scale factor from a triangle with sides 3, 4, 5 to a similar triangle with sides 6, 8, 10?
22. If a recipe calls for a ratio of butter to sugar of 1:4, how much sugar is needed for 8 cups of butter?
23. A recipe uses a ratio of flour to sugar of $5:2$. If you use 30 cups of flour, how many cups of sugar are needed to keep the ratio the same?
24. The ratio of red marbles to green marbles is $5:6$. If there are 55 red marbles, how many green marbles are there?
25. A paint mixture uses a ratio of $3:2$ for blue paint to white paint. If a painter uses $18$ cups of blue paint, how many cups of white paint are needed to keep the mixture in the same ratio?
26. A painting is reduced with a scale factor of 1/3. If the original height is 9 feet, what is the height of the reduced painting?
27. On a map, $\frac{1}{2}$ inch represents 15 miles. If two cities are 3.5 inches apart on the map, what is the actual distance, in miles, between them?
28. A cyclist travels at 15 miles per hour. What is the speed in feet per minute? (1 mile = 5,280 feet)
29. What is the value of $x$ in the proportion $\frac{4}{x}=\frac{10}{35}$?
30. If $\frac{5}{x} = \frac{15}{18}$, what is the value of $x$?
31. The ratio of red balls to green balls in a box is 2:5. If there are 20 red balls, how many green balls are there?
32. If the ratio of A to B is 6:7, what is A when B = 21?
33. Which of the following ratios is equivalent to $5:4$?
34. The scale factor from model A to model B is 3. If the length of model A is 5 cm, what is the length of model B?
35. A model airplane is built to a scale of 1:100. If the real airplane is 30 meters in wingspan, what is the wingspan of the model?
36. A recipe requires a ratio of 2 cups of milk to 3 cups of flour. If 8 cups of milk are used, how much flour is needed?
37. The ratio of kids to adults at a party is 3:4. If there are 12 kids, how many adults are there?
38. Which of the following ratios is equivalent to $7:3$?
39. If $\frac{8}{16} = \frac{x}{32}$, what is the value of $x$?
40. In a mixture of paint, the ratio of blue to yellow is 2:3. If there are 6 liters of blue paint, how much yellow paint is needed?
41. A map has a scale of 1:5000. If a road measures 10 cm on the map, what is the actual length of the road?
42. A scale model of a ship is built at a scale of 1:200. If the actual ship is 100 meters long, how long is the model?
43. If a recipe requires a ratio of 3 cups of flour to 2 cups of sugar, how much flour is needed for 12 cups of sugar?
44. In a school, the ratio of teachers to students is 1:20. If there are 5 teachers, how many students are there?
45. A photograph is enlarged with a scale factor of 2. If the original width is 6 inches, what is the width of the enlarged photograph?
46. The ratio of apples to oranges in a basket is $3:2$. If there are 15 apples, how many oranges are there?
47. What is the value of $x$ in the proportion $\frac{9}{x} = \frac{3}{2}$?
48. If the ratio of red to blue marbles is 4:7 and there are 28 blue marbles, how many red marbles are there?
49. What is the value of $x$ in the proportion $\frac{4}{5} = \frac{x}{15}$?
50. If $\frac{10}{x} = \frac{25}{30}$, what is the value of $x$?
51. If $\frac{7}{x} = \frac{21}{9}$, what is the value of $x$?
52. A toy is made with a scale of 1:50. If the actual building is 100 meters tall, how tall is the toy model?
53. A rectangle has a length to width ratio of 5:3. If the width is 9 cm, what is the length?
54. What is the scale factor from a model to the actual object if the model is 3 cm and the object is 15 cm?
55. If the ratio of cats to dogs in a shelter is 3:5 and there are 15 cats, how many dogs are there?
56. The ratio of cats to dogs at an animal shelter is $2:5$. If there are 21 animals total (only cats and dogs), how many cats are there?
57. Which ratio is equivalent to $9:4$?
58. Which ratio is equivalent to $4:7$?
59. The ratio of red marbles to blue marbles in a bag is $3:5$. If there are $40$ blue marbles, how many red marbles are in the bag?
60. In a class, the ratio of students wearing sneakers to students wearing boots is $9:6$. If there are $45$ students wearing sneakers, how many students are wearing boots?
61. A model car is built at a scale of $1:12$ (model:real). If the real car is $180$ inches long, how long is the model in inches?
62. What is the value of $x$ in the proportion $\dfrac{7}{x}=\dfrac{21}{18}$? (Use cross-multiplication: if $\dfrac{a}{b}=\dfrac{c}{d}$, then $ad=bc$.)
63. A recipe uses a ratio of flour to sugar of $4:1$. If you use $3$ cups of sugar, how many cups of flour are needed to keep the same ratio?
64. The ratio of cats to dogs at a shelter is $5:4$. If there are $28$ dogs, how many cats are there?
65. A map uses the scale $1\text{ inch} : 5\text{ miles}$. Two towns are $7$ inches apart on the map. What is the actual distance between the towns in miles?
66. A paint mixture uses a ratio of blue to yellow of $3:2$. If the artist uses $18$ cups of blue paint, how many cups of yellow paint are needed to keep the same ratio?
67. In a bag of marbles, the ratio of red to blue marbles is $3:5$. If there are $40$ blue marbles, how many red marbles are there?
68. A map uses the scale $1\text{ inch} : 4\text{ miles}$. Two towns are $3.5$ inches apart on the map. How many miles apart are the towns in real life?
69. A recipe mixes lemon juice and water in the ratio $2:7$ (lemon:water). If you use $21$ cups of water, how many cups of lemon juice are needed to keep the same ratio?
70. A car is traveling at a constant speed of 60 miles per hour. How many feet does the car travel in 3 seconds? (Note: $1 \text{ mile} = 5,280 \text{ feet}$)
71. On a map, 1.5 inches represents 40 miles. If two cities are 6 inches apart on the map, what is the actual distance between them, in miles?
72. A rope of length 150 feet is cut into three pieces with lengths in the ratio 2:3:5. What is the length, in feet, of the longest piece?
73. If a model car has a scale of 1:20 and the model is 15 cm long, how long is the actual car?
74. A model car is built to a scale of $1:18$, meaning 1 inch on the model represents 18 inches on the real car. If the real car is 162 inches long, how long is the model car in inches?
75. What is the value of $x$ in the proportion $\frac{3}{5}=\frac{x}{20}$? (Use cross-multiplication: if $\frac{a}{b}=\frac{c}{d}$, then $ad=bc$.)
76. What is the value of $x$ in the proportion $\frac{7}{9}=\frac{21}{x}$? (If $\frac{a}{b}=\frac{c}{d}$, then $ad=bc$.)
77. A map uses a scale of $1\text{ cm}:5\text{ km}$. Two towns are 7 cm apart on the map. What is the actual distance between the towns in kilometers?
78. What is the value of $x$ in the proportion $\frac{x}{14}=\frac{5}{7}$?
79. If the ratio of boys to girls in a class is 4:5 and there are 20 boys, how many girls are in the class?
80. A sports drink is mixed in a ratio of water to concentrate of $7:1$. If you have 6 cups of concentrate, how many cups of water do you need?
81. On a map, $\frac{1}{2}$ inch represents 15 miles. If two cities are 3.5 inches apart on the map, what is the actual distance, in miles, between them?