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Finding the Fourth Proportional to 155.31, 232.62 and 86.65

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Solution

The fourth proportional to 155.31, 232.62 and 86.65 is: 129.78

Step by Step Solution

  1. Step 1: Write the proportion equation
    155.31 : 232.62 = 86.65 : x
  2. Step 2: Convert to fraction form
    155.31/232.62 = 86.65/x
  3. Step 3: Cross multiply
    155.31x = 232.62 × 86.65
  4. Step 4: Simplify right side
    155.31x = 20,156.52
  5. Step 5: Solve for x
    x = 20,156.52/155.31
  6. Step 6: Final answer
    x = 129.78

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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.