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Finding the Fourth Proportional to 628.08, 867.11 and 487.89

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Solution

The fourth proportional to 628.08, 867.11 and 487.89 is: 673.56

Step by Step Solution

  1. Step 1: Write the proportion equation
    628.08 : 867.11 = 487.89 : x
  2. Step 2: Convert to fraction form
    628.08/867.11 = 487.89/x
  3. Step 3: Cross multiply
    628.08x = 867.11 × 487.89
  4. Step 4: Simplify right side
    628.08x = 423,051.86
  5. Step 5: Solve for x
    x = 423,051.86/628.08
  6. Step 6: Final answer
    x = 673.56

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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.