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Finding the Fourth Proportional to 408.91, 613.91 and 318.19

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Solution

The fourth proportional to 408.91, 613.91 and 318.19 is: 477.71

Step by Step Solution

  1. Step 1: Write the proportion equation
    408.91 : 613.91 = 318.19 : x
  2. Step 2: Convert to fraction form
    408.91/613.91 = 318.19/x
  3. Step 3: Cross multiply
    408.91x = 613.91 × 318.19
  4. Step 4: Simplify right side
    408.91x = 195,338.43
  5. Step 5: Solve for x
    x = 195,338.43/408.91
  6. Step 6: Final answer
    x = 477.71

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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.