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Finding the Fourth Proportional to 329.85, 494.81 and 86.39

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Solution

The fourth proportional to 329.85, 494.81 and 86.39 is: 129.59

Step by Step Solution

  1. Step 1: Write the proportion equation
    329.85 : 494.81 = 86.39 : x
  2. Step 2: Convert to fraction form
    329.85/494.81 = 86.39/x
  3. Step 3: Cross multiply
    329.85x = 494.81 × 86.39
  4. Step 4: Simplify right side
    329.85x = 42,743.73
  5. Step 5: Solve for x
    x = 42,743.73/329.85
  6. Step 6: Final answer
    x = 129.59

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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.