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Finding the Fourth Proportional to 680.43, 939.31 and 400.57

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Solution

The fourth proportional to 680.43, 939.31 and 400.57 is: 552.98

Step by Step Solution

  1. Step 1: Write the proportion equation
    680.43 : 939.31 = 400.57 : x
  2. Step 2: Convert to fraction form
    680.43/939.31 = 400.57/x
  3. Step 3: Cross multiply
    680.43x = 939.31 × 400.57
  4. Step 4: Simplify right side
    680.43x = 376,259.58
  5. Step 5: Solve for x
    x = 376,259.58/680.43
  6. Step 6: Final answer
    x = 552.98

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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.