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Finding the Fourth Proportional to 680, 938.56 and 418.20

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Solution

The fourth proportional to 680, 938.56 and 418.20 is: 577.21

Step by Step Solution

  1. Step 1: Write the proportion equation
    680 : 938.56 = 418.20 : x
  2. Step 2: Convert to fraction form
    680/938.56 = 418.20/x
  3. Step 3: Cross multiply
    680x = 938.56 × 418.20
  4. Step 4: Simplify right side
    680x = 392,505.79
  5. Step 5: Solve for x
    x = 392,505.79/680
  6. Step 6: Final answer
    x = 577.21

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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.