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Finding the Fourth Proportional to 80.25, 120.39 and 26.13

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Solution

The fourth proportional to 80.25, 120.39 and 26.13 is: 39.20

Step by Step Solution

  1. Step 1: Write the proportion equation
    80.25 : 120.39 = 26.13 : x
  2. Step 2: Convert to fraction form
    80.25/120.39 = 26.13/x
  3. Step 3: Cross multiply
    80.25x = 120.39 × 26.13
  4. Step 4: Simplify right side
    80.25x = 3,145.79
  5. Step 5: Solve for x
    x = 3,145.79/80.25
  6. Step 6: Final answer
    x = 39.20

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.