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Finding the Fourth Proportional to 87.34, 130.32 and 77.55

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Solution

The fourth proportional to 87.34, 130.32 and 77.55 is: 115.70

Step by Step Solution

  1. Step 1: Write the proportion equation
    87.34 : 130.32 = 77.55 : x
  2. Step 2: Convert to fraction form
    87.34/130.32 = 77.55/x
  3. Step 3: Cross multiply
    87.34x = 130.32 × 77.55
  4. Step 4: Simplify right side
    87.34x = 10,105.66
  5. Step 5: Solve for x
    x = 10,105.66/87.34
  6. Step 6: Final answer
    x = 115.70

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Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.