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Finding the Fourth Proportional to 680.28, 938.68 and 385.48

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Solution

The fourth proportional to 680.28, 938.68 and 385.48 is: 531.90

Step by Step Solution

  1. Step 1: Write the proportion equation
    680.28 : 938.68 = 385.48 : x
  2. Step 2: Convert to fraction form
    680.28/938.68 = 385.48/x
  3. Step 3: Cross multiply
    680.28x = 938.68 × 385.48
  4. Step 4: Simplify right side
    680.28x = 361,842.37
  5. Step 5: Solve for x
    x = 361,842.37/680.28
  6. Step 6: Final answer
    x = 531.90

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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.