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Finding the Third Proportional to 80.30 and 128.11

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Solution

The third proportional to 80.30 and 128.11 is: 204.39

Step by Step Solution

  1. Step 1: Write the proportion equation
    80.30 : 128.11 = 128.11 : x
  2. Step 2: Convert to fraction form
    80.30/128.11 = 128.11/x
  3. Step 3: Cross multiply
    80.30x = 128.11 × 128.11
  4. Step 4: Simplify right side
    80.30x = 16,412.01
  5. Step 5: Solve for x
    x = 16,412.01/80.30
  6. Step 6: Final answer
    x = 204.39

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Why These Related Problems?

These problems maintain the same ratio (1.60) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.