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Finding the Fourth Proportional to 487.20, 671.73 and 321.12

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Solution

The fourth proportional to 487.20, 671.73 and 321.12 is: 442.75

Step by Step Solution

  1. Step 1: Write the proportion equation
    487.20 : 671.73 = 321.12 : x
  2. Step 2: Convert to fraction form
    487.20/671.73 = 321.12/x
  3. Step 3: Cross multiply
    487.20x = 671.73 × 321.12
  4. Step 4: Simplify right side
    487.20x = 215,705.94
  5. Step 5: Solve for x
    x = 215,705.94/487.20
  6. Step 6: Final answer
    x = 442.75

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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.