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Finding the Fourth Proportional to 680.42, 938.97 and 400.65

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Solution

The fourth proportional to 680.42, 938.97 and 400.65 is: 552.90

Step by Step Solution

  1. Step 1: Write the proportion equation
    680.42 : 938.97 = 400.65 : x
  2. Step 2: Convert to fraction form
    680.42/938.97 = 400.65/x
  3. Step 3: Cross multiply
    680.42x = 938.97 × 400.65
  4. Step 4: Simplify right side
    680.42x = 376,198.33
  5. Step 5: Solve for x
    x = 376,198.33/680.42
  6. Step 6: Final answer
    x = 552.90

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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.