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Finding the Fourth Proportional to 658.44, 987.81 and 219.72

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Solution

The fourth proportional to 658.44, 987.81 and 219.72 is: 329.63

Step by Step Solution

  1. Step 1: Write the proportion equation
    658.44 : 987.81 = 219.72 : x
  2. Step 2: Convert to fraction form
    658.44/987.81 = 219.72/x
  3. Step 3: Cross multiply
    658.44x = 987.81 × 219.72
  4. Step 4: Simplify right side
    658.44x = 217,041.61
  5. Step 5: Solve for x
    x = 217,041.61/658.44
  6. Step 6: Final answer
    x = 329.63

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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.