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Finding the Fourth Proportional to 658.74, 987.28 and 311.61

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Solution

The fourth proportional to 658.74, 987.28 and 311.61 is: 467.02

Step by Step Solution

  1. Step 1: Write the proportion equation
    658.74 : 987.28 = 311.61 : x
  2. Step 2: Convert to fraction form
    658.74/987.28 = 311.61/x
  3. Step 3: Cross multiply
    658.74x = 987.28 × 311.61
  4. Step 4: Simplify right side
    658.74x = 307,646.32
  5. Step 5: Solve for x
    x = 307,646.32/658.74
  6. Step 6: Final answer
    x = 467.02

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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.