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Finding the Fourth Proportional to 658.80, 987.98 and 219.95

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Solution

The fourth proportional to 658.80, 987.98 and 219.95 is: 329.85

Step by Step Solution

  1. Step 1: Write the proportion equation
    658.80 : 987.98 = 219.95 : x
  2. Step 2: Convert to fraction form
    658.80/987.98 = 219.95/x
  3. Step 3: Cross multiply
    658.80x = 987.98 × 219.95
  4. Step 4: Simplify right side
    658.80x = 217,305.10
  5. Step 5: Solve for x
    x = 217,305.10/658.80
  6. Step 6: Final answer
    x = 329.85

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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.