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Finding the Fourth Proportional to 627.80, 866.26 and 391.71

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Solution

The fourth proportional to 627.80, 866.26 and 391.71 is: 540.49

Step by Step Solution

  1. Step 1: Write the proportion equation
    627.80 : 866.26 = 391.71 : x
  2. Step 2: Convert to fraction form
    627.80/866.26 = 391.71/x
  3. Step 3: Cross multiply
    627.80x = 866.26 × 391.71
  4. Step 4: Simplify right side
    627.80x = 339,316.41
  5. Step 5: Solve for x
    x = 339,316.41/627.80
  6. Step 6: Final answer
    x = 540.49

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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.