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Finding the Fourth Proportional to 638.02, 879.96 and 404.74

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Solution

The fourth proportional to 638.02, 879.96 and 404.74 is: 558.22

Step by Step Solution

  1. Step 1: Write the proportion equation
    638.02 : 879.96 = 404.74 : x
  2. Step 2: Convert to fraction form
    638.02/879.96 = 404.74/x
  3. Step 3: Cross multiply
    638.02x = 879.96 × 404.74
  4. Step 4: Simplify right side
    638.02x = 356,155.01
  5. Step 5: Solve for x
    x = 356,155.01/638.02
  6. Step 6: Final answer
    x = 558.22

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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.