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Finding the Third Proportional to 3.85 and 7.70

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Solution

The third proportional to 3.85 and 7.70 is: 15.39

Step by Step Solution

  1. Step 1: Write the proportion equation
    3.85 : 7.70 = 7.70 : x
  2. Step 2: Convert to fraction form
    3.85/7.70 = 7.70/x
  3. Step 3: Cross multiply
    3.85x = 7.70 × 7.70
  4. Step 4: Simplify right side
    3.85x = 59.25
  5. Step 5: Solve for x
    x = 59.25/3.85
  6. Step 6: Final answer
    x = 15.39

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1.5x scale

Why These Related Problems?

These problems maintain the same ratio (2.00) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.