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Finding the Fourth Proportional to 408.21, 609.99 and 398.98

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Solution

The fourth proportional to 408.21, 609.99 and 398.98 is: 596.20

Step by Step Solution

  1. Step 1: Write the proportion equation
    408.21 : 609.99 = 398.98 : x
  2. Step 2: Convert to fraction form
    408.21/609.99 = 398.98/x
  3. Step 3: Cross multiply
    408.21x = 609.99 × 398.98
  4. Step 4: Simplify right side
    408.21x = 243,375.32
  5. Step 5: Solve for x
    x = 243,375.32/408.21
  6. Step 6: Final answer
    x = 596.20

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Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.