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Finding the Fourth Proportional to 398.62, 550.38 and 305.86

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Solution

The fourth proportional to 398.62, 550.38 and 305.86 is: 422.31

Step by Step Solution

  1. Step 1: Write the proportion equation
    398.62 : 550.38 = 305.86 : x
  2. Step 2: Convert to fraction form
    398.62/550.38 = 305.86/x
  3. Step 3: Cross multiply
    398.62x = 550.38 × 305.86
  4. Step 4: Simplify right side
    398.62x = 168,339.23
  5. Step 5: Solve for x
    x = 168,339.23/398.62
  6. Step 6: Final answer
    x = 422.31

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.