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Finding the Fourth Proportional to 658.36, 987.18 and 311.28

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Solution

The fourth proportional to 658.36, 987.18 and 311.28 is: 466.75

Step by Step Solution

  1. Step 1: Write the proportion equation
    658.36 : 987.18 = 311.28 : x
  2. Step 2: Convert to fraction form
    658.36/987.18 = 311.28/x
  3. Step 3: Cross multiply
    658.36x = 987.18 × 311.28
  4. Step 4: Simplify right side
    658.36x = 307,289.39
  5. Step 5: Solve for x
    x = 307,289.39/658.36
  6. Step 6: Final answer
    x = 466.75

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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.