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Finding the Fourth Proportional to 680.72, 939.59 and 400.97

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Solution

The fourth proportional to 680.72, 939.59 and 400.97 is: 553.45

Step by Step Solution

  1. Step 1: Write the proportion equation
    680.72 : 939.59 = 400.97 : x
  2. Step 2: Convert to fraction form
    680.72/939.59 = 400.97/x
  3. Step 3: Cross multiply
    680.72x = 939.59 × 400.97
  4. Step 4: Simplify right side
    680.72x = 376,747.40
  5. Step 5: Solve for x
    x = 376,747.40/680.72
  6. Step 6: Final answer
    x = 553.45

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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.