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Finding the Fourth Proportional to 658.25, 987.38 and 398.88

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Solution

The fourth proportional to 658.25, 987.38 and 398.88 is: 598.32

Step by Step Solution

  1. Step 1: Write the proportion equation
    658.25 : 987.38 = 398.88 : x
  2. Step 2: Convert to fraction form
    658.25/987.38 = 398.88/x
  3. Step 3: Cross multiply
    658.25x = 987.38 × 398.88
  4. Step 4: Simplify right side
    658.25x = 393,844.14
  5. Step 5: Solve for x
    x = 393,844.14/658.25
  6. Step 6: Final answer
    x = 598.32

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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.