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Finding the Fourth Proportional to 680.30, 938.74 and 400.66

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Solution

The fourth proportional to 680.30, 938.74 and 400.66 is: 552.87

Step by Step Solution

  1. Step 1: Write the proportion equation
    680.30 : 938.74 = 400.66 : x
  2. Step 2: Convert to fraction form
    680.30/938.74 = 400.66/x
  3. Step 3: Cross multiply
    680.30x = 938.74 × 400.66
  4. Step 4: Simplify right side
    680.30x = 376,115.57
  5. Step 5: Solve for x
    x = 376,115.57/680.30
  6. Step 6: Final answer
    x = 552.87

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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.