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Finding the Fourth Proportional to 87.07, 129.85 and 82.28

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Solution

The fourth proportional to 87.07, 129.85 and 82.28 is: 122.70

Step by Step Solution

  1. Step 1: Write the proportion equation
    87.07 : 129.85 = 82.28 : x
  2. Step 2: Convert to fraction form
    87.07/129.85 = 82.28/x
  3. Step 3: Cross multiply
    87.07x = 129.85 × 82.28
  4. Step 4: Simplify right side
    87.07x = 10,683.65
  5. Step 5: Solve for x
    x = 10,683.65/87.07
  6. Step 6: Final answer
    x = 122.70

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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.