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Finding the Fourth Proportional to 87.40, 130.55 and 84.97

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Solution

The fourth proportional to 87.40, 130.55 and 84.97 is: 126.92

Step by Step Solution

  1. Step 1: Write the proportion equation
    87.40 : 130.55 = 84.97 : x
  2. Step 2: Convert to fraction form
    87.40/130.55 = 84.97/x
  3. Step 3: Cross multiply
    87.40x = 130.55 × 84.97
  4. Step 4: Simplify right side
    87.40x = 11,092.83
  5. Step 5: Solve for x
    x = 11,092.83/87.40
  6. Step 6: Final answer
    x = 126.92

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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.