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Finding the Fourth Proportional to 628.80, 867.20 and 379.84

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Solution

The fourth proportional to 628.80, 867.20 and 379.84 is: 523.85

Step by Step Solution

  1. Step 1: Write the proportion equation
    628.80 : 867.20 = 379.84 : x
  2. Step 2: Convert to fraction form
    628.80/867.20 = 379.84/x
  3. Step 3: Cross multiply
    628.80x = 867.20 × 379.84
  4. Step 4: Simplify right side
    628.80x = 329,397.25
  5. Step 5: Solve for x
    x = 329,397.25/628.80
  6. Step 6: Final answer
    x = 523.85

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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.