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Finding the Fourth Proportional to 638.80, 879.93 and 451.96

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Solution

The fourth proportional to 638.80, 879.93 and 451.96 is: 622.56

Step by Step Solution

  1. Step 1: Write the proportion equation
    638.80 : 879.93 = 451.96 : x
  2. Step 2: Convert to fraction form
    638.80/879.93 = 451.96/x
  3. Step 3: Cross multiply
    638.80x = 879.93 × 451.96
  4. Step 4: Simplify right side
    638.80x = 397,693.16
  5. Step 5: Solve for x
    x = 397,693.16/638.80
  6. Step 6: Final answer
    x = 622.56

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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.