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Finding the Fourth Proportional to 87.13, 120.19 and 68.65

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Solution

The fourth proportional to 87.13, 120.19 and 68.65 is: 94.70

Step by Step Solution

  1. Step 1: Write the proportion equation
    87.13 : 120.19 = 68.65 : x
  2. Step 2: Convert to fraction form
    87.13/120.19 = 68.65/x
  3. Step 3: Cross multiply
    87.13x = 120.19 × 68.65
  4. Step 4: Simplify right side
    87.13x = 8,251.04
  5. Step 5: Solve for x
    x = 8,251.04/87.13
  6. Step 6: Final answer
    x = 94.70

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.