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Finding the Fourth Proportional to 87.17, 130.57 and 54.68

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Solution

The fourth proportional to 87.17, 130.57 and 54.68 is: 81.90

Step by Step Solution

  1. Step 1: Write the proportion equation
    87.17 : 130.57 = 54.68 : x
  2. Step 2: Convert to fraction form
    87.17/130.57 = 54.68/x
  3. Step 3: Cross multiply
    87.17x = 130.57 × 54.68
  4. Step 4: Simplify right side
    87.17x = 7,139.57
  5. Step 5: Solve for x
    x = 7,139.57/87.17
  6. Step 6: Final answer
    x = 81.90

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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.