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Finding the Fourth Proportional to 320.88, 481.29 and 86.61

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Solution

The fourth proportional to 320.88, 481.29 and 86.61 is: 129.91

Step by Step Solution

  1. Step 1: Write the proportion equation
    320.88 : 481.29 = 86.61 : x
  2. Step 2: Convert to fraction form
    320.88/481.29 = 86.61/x
  3. Step 3: Cross multiply
    320.88x = 481.29 × 86.61
  4. Step 4: Simplify right side
    320.88x = 41,684.53
  5. Step 5: Solve for x
    x = 41,684.53/320.88
  6. Step 6: Final answer
    x = 129.91

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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.