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Finding the Third Proportional to 5.20 and 8.16

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Solution

The third proportional to 5.20 and 8.16 is: 12.79

Step by Step Solution

  1. Step 1: Write the proportion equation
    5.20 : 8.16 = 8.16 : x
  2. Step 2: Convert to fraction form
    5.20/8.16 = 8.16/x
  3. Step 3: Cross multiply
    5.20x = 8.16 × 8.16
  4. Step 4: Simplify right side
    5.20x = 66.52
  5. Step 5: Solve for x
    x = 66.52/5.20
  6. Step 6: Final answer
    x = 12.79

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Why These Related Problems?

These problems maintain the same ratio (1.57) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.