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Finding the Fourth Proportional to 286.03, 396.31 and 279.88

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Solution

The fourth proportional to 286.03, 396.31 and 279.88 is: 387.79

Step by Step Solution

  1. Step 1: Write the proportion equation
    286.03 : 396.31 = 279.88 : x
  2. Step 2: Convert to fraction form
    286.03/396.31 = 279.88/x
  3. Step 3: Cross multiply
    286.03x = 396.31 × 279.88
  4. Step 4: Simplify right side
    286.03x = 110,918.54
  5. Step 5: Solve for x
    x = 110,918.54/286.03
  6. Step 6: Final answer
    x = 387.79

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Why These Related Problems?

These problems maintain the same ratio (1.39) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.