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Finding the Fourth Proportional to 658.42, 987.96 and 398.95

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Solution

The fourth proportional to 658.42, 987.96 and 398.95 is: 598.62

Step by Step Solution

  1. Step 1: Write the proportion equation
    658.42 : 987.96 = 398.95 : x
  2. Step 2: Convert to fraction form
    658.42/987.96 = 398.95/x
  3. Step 3: Cross multiply
    658.42x = 987.96 × 398.95
  4. Step 4: Simplify right side
    658.42x = 394,146.64
  5. Step 5: Solve for x
    x = 394,146.64/658.42
  6. Step 6: Final answer
    x = 598.62

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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.