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Finding the Fourth Proportional to 680.47, 939.09 and 400.71

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Solution

The fourth proportional to 680.47, 939.09 and 400.71 is: 553.01

Step by Step Solution

  1. Step 1: Write the proportion equation
    680.47 : 939.09 = 400.71 : x
  2. Step 2: Convert to fraction form
    680.47/939.09 = 400.71/x
  3. Step 3: Cross multiply
    680.47x = 939.09 × 400.71
  4. Step 4: Simplify right side
    680.47x = 376,307.78
  5. Step 5: Solve for x
    x = 376,307.78/680.47
  6. Step 6: Final answer
    x = 553.01

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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.