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Finding the Fourth Proportional to 87.15, 130.04 and 85.10

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Solution

The fourth proportional to 87.15, 130.04 and 85.10 is: 126.97

Step by Step Solution

  1. Step 1: Write the proportion equation
    87.15 : 130.04 = 85.10 : x
  2. Step 2: Convert to fraction form
    87.15/130.04 = 85.10/x
  3. Step 3: Cross multiply
    87.15x = 130.04 × 85.10
  4. Step 4: Simplify right side
    87.15x = 11,065.65
  5. Step 5: Solve for x
    x = 11,065.65/87.15
  6. Step 6: Final answer
    x = 126.97

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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.