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Finding the Fourth Proportional to 624.80, 861.92 and 438.72

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Solution

The fourth proportional to 624.80, 861.92 and 438.72 is: 605.22

Step by Step Solution

  1. Step 1: Write the proportion equation
    624.80 : 861.92 = 438.72 : x
  2. Step 2: Convert to fraction form
    624.80/861.92 = 438.72/x
  3. Step 3: Cross multiply
    624.80x = 861.92 × 438.72
  4. Step 4: Simplify right side
    624.80x = 378,141.54
  5. Step 5: Solve for x
    x = 378,141.54/624.80
  6. Step 6: Final answer
    x = 605.22

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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.