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Finding the Fourth Proportional to 638.94, 875.91 and 628.86

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Solution

The fourth proportional to 638.94, 875.91 and 628.86 is: 862.09

Step by Step Solution

  1. Step 1: Write the proportion equation
    638.94 : 875.91 = 628.86 : x
  2. Step 2: Convert to fraction form
    638.94/875.91 = 628.86/x
  3. Step 3: Cross multiply
    638.94x = 875.91 × 628.86
  4. Step 4: Simplify right side
    638.94x = 550,824.76
  5. Step 5: Solve for x
    x = 550,824.76/638.94
  6. Step 6: Final answer
    x = 862.09

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Why These Related Problems?

These problems maintain the same ratio (1.37) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.