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Finding the Fourth Proportional to 680.08, 938.40 and 385.32

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Solution

The fourth proportional to 680.08, 938.40 and 385.32 is: 531.68

Step by Step Solution

  1. Step 1: Write the proportion equation
    680.08 : 938.40 = 385.32 : x
  2. Step 2: Convert to fraction form
    680.08/938.40 = 385.32/x
  3. Step 3: Cross multiply
    680.08x = 938.40 × 385.32
  4. Step 4: Simplify right side
    680.08x = 361,584.29
  5. Step 5: Solve for x
    x = 361,584.29/680.08
  6. Step 6: Final answer
    x = 531.68

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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.