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Finding the Fourth Proportional to 628.39, 867.11 and 379.72

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Solution

The fourth proportional to 628.39, 867.11 and 379.72 is: 523.97

Step by Step Solution

  1. Step 1: Write the proportion equation
    628.39 : 867.11 = 379.72 : x
  2. Step 2: Convert to fraction form
    628.39/867.11 = 379.72/x
  3. Step 3: Cross multiply
    628.39x = 867.11 × 379.72
  4. Step 4: Simplify right side
    628.39x = 329,259.01
  5. Step 5: Solve for x
    x = 329,259.01/628.39
  6. Step 6: Final answer
    x = 523.97

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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.