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Finding the Fourth Proportional to 87.43, 130.61 and 77.39

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Solution

The fourth proportional to 87.43, 130.61 and 77.39 is: 115.62

Step by Step Solution

  1. Step 1: Write the proportion equation
    87.43 : 130.61 = 77.39 : x
  2. Step 2: Convert to fraction form
    87.43/130.61 = 77.39/x
  3. Step 3: Cross multiply
    87.43x = 130.61 × 77.39
  4. Step 4: Simplify right side
    87.43x = 10,107.91
  5. Step 5: Solve for x
    x = 10,107.91/87.43
  6. Step 6: Final answer
    x = 115.62

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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.