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Finding the Fourth Proportional to 658.80, 988.62 and 398.76

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Solution

The fourth proportional to 658.80, 988.62 and 398.76 is: 598.39

Step by Step Solution

  1. Step 1: Write the proportion equation
    658.80 : 988.62 = 398.76 : x
  2. Step 2: Convert to fraction form
    658.80/988.62 = 398.76/x
  3. Step 3: Cross multiply
    658.80x = 988.62 × 398.76
  4. Step 4: Simplify right side
    658.80x = 394,222.11
  5. Step 5: Solve for x
    x = 394,222.11/658.80
  6. Step 6: Final answer
    x = 598.39

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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.