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Finding the Fourth Proportional to 451.62, 621.81 and 398.39

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Solution

The fourth proportional to 451.62, 621.81 and 398.39 is: 548.51

Step by Step Solution

  1. Step 1: Write the proportion equation
    451.62 : 621.81 = 398.39 : x
  2. Step 2: Convert to fraction form
    451.62/621.81 = 398.39/x
  3. Step 3: Cross multiply
    451.62x = 621.81 × 398.39
  4. Step 4: Simplify right side
    451.62x = 247,719.78
  5. Step 5: Solve for x
    x = 247,719.78/451.62
  6. Step 6: Final answer
    x = 548.51

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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.