Lesson 1.1: Understanding Ratios
Example: A class has 10 boys and 15 girls. What is the ratio of boys to girls?
Step 1: Write the ratio as a fraction → 10/15.
Step 2: Simplify → 2/3.
Answer: 2:3 (two to three).
Quiz: If there are 8 apples and 12 oranges, what is the ratio of apples to oranges?
How to get the right answer:
Step 1: Write the ratio as a fraction → **8/12**.
Step 2: Simplify → **Divide both by 4** → **2/3**.
So, the correct answer is **A) 2:3**.
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Lesson 1.2: Finding Equivalent Ratios
Example: Find two equivalent ratios for 4:6.
Step 1: Multiply both terms by 2 → 8:12.
Step 2: Divide both terms by 2 → 2:3.
Answer: 8:12 and 2:3 are equivalent ratios.
Quiz: What is an equivalent ratio of 5:10?
How to get the right answer:
Step 1: Multiply **both numbers** by 2 → **10:20**.
Step 2: Divide **both numbers** by 5 → **1:2 (not in the choices).**
So, the correct answer is **A) 10:20**.
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Lesson 1.3: Solving Proportion Problems
Example: If 3 pencils cost $1.50, how much do 9 pencils cost?
Step 1: Set up proportion → 3/1.50 = 9/x.
Step 2: Cross multiply → 3x = 13.50.
Step 3: Solve for x → x = $4.50.
Answer: 9 pencils cost $4.50.
Quiz: If 4 apples cost $2, how much do 12 apples cost?
How to get the right answer:
Step 1: Set up proportion → **4 apples/$2 = 12 apples/x**.
Step 2: Cross multiply → **4x = 24**.
Step 3: Solve for x → **x = $6**.
So, the correct answer is **A) $6**.
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