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Finding the Fourth Proportional to 638.92, 885.55 and 628.48

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Solution

The fourth proportional to 638.92, 885.55 and 628.48 is: 871.08

Step by Step Solution

  1. Step 1: Write the proportion equation
    638.92 : 885.55 = 628.48 : x
  2. Step 2: Convert to fraction form
    638.92/885.55 = 628.48/x
  3. Step 3: Cross multiply
    638.92x = 885.55 × 628.48
  4. Step 4: Simplify right side
    638.92x = 556,550.46
  5. Step 5: Solve for x
    x = 556,550.46/638.92
  6. Step 6: Final answer
    x = 871.08

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Why These Related Problems?

These problems maintain the same ratio (1.39) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.