Everyday Life Applications of Comparing Ratios (7th Grade Examples)

📚 Quick Study Guide

• ⚖️ A ratio compares two quantities. We can write it as a fraction, using a colon, or with the word "to".
• ➗ Comparing ratios means checking if two ratios are equivalent. If they are, they form a proportion.
• 🍕 In everyday life, we use ratios to scale recipes, calculate prices, understand maps, and more!
• ✍️ To check if two ratios are equal, you can cross-multiply. If the cross-products are equal, the ratios are equivalent. For example, $\frac{a}{b} = \frac{c}{d}$ if and only if $ad = bc$.
• 🗺️ Scale drawings and maps use ratios to represent real-world distances. Understanding these ratios helps us interpret the drawings correctly.

Practice Quiz

1. Question 1: A recipe calls for 2 cups of flour for every 3 eggs. If you want to use 6 eggs, how many cups of flour do you need?
   1. 1 cup
   2. 4 cups
   3. 9 cups
   4. 12 cups
2. Question 2: At a store, 5 apples cost $2. How much would 15 apples cost?
   1. $4
   2. $6
   3. $8
   4. $10
3. Question 3: A map has a scale of 1 inch = 20 miles. If two cities are 3 inches apart on the map, what is the actual distance between them?
   1. 10 miles
   2. 23 miles
   3. 60 miles
   4. 80 miles
4. Question 4: You can run 2 miles in 20 minutes. At this rate, how long will it take you to run 5 miles?
   1. 30 minutes
   2. 40 minutes
   3. 50 minutes
   4. 60 minutes
5. Question 5: A painter mixes 3 parts blue paint with 2 parts yellow paint to make green. If he uses 6 gallons of blue paint, how many gallons of yellow paint does he need?
   1. 2 gallons
   2. 4 gallons
   3. 5 gallons
   4. 9 gallons
6. Question 6: A school has a student to teacher ratio of 20:1. If there are 300 students, how many teachers are there?
   1. 10
   2. 15
   3. 20
   4. 25
7. Question 7: A store sells 3 oranges for $1. How many oranges can you buy with $5?
   1. 8
   2. 12
   3. 15
   4. 18