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Finding the Fourth Proportional to 658.39, 987.56 and 219.61

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Solution

The fourth proportional to 658.39, 987.56 and 219.61 is: 329.40

Step by Step Solution

  1. Step 1: Write the proportion equation
    658.39 : 987.56 = 219.61 : x
  2. Step 2: Convert to fraction form
    658.39/987.56 = 219.61/x
  3. Step 3: Cross multiply
    658.39x = 987.56 × 219.61
  4. Step 4: Simplify right side
    658.39x = 216,876.95
  5. Step 5: Solve for x
    x = 216,876.95/658.39
  6. Step 6: Final answer
    x = 329.40

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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.