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Finding the Fourth Proportional to 287.24, 391.09 and 286.33

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Solution

The fourth proportional to 287.24, 391.09 and 286.33 is: 389.85

Step by Step Solution

  1. Step 1: Write the proportion equation
    287.24 : 391.09 = 286.33 : x
  2. Step 2: Convert to fraction form
    287.24/391.09 = 286.33/x
  3. Step 3: Cross multiply
    287.24x = 391.09 × 286.33
  4. Step 4: Simplify right side
    287.24x = 111,982.49
  5. Step 5: Solve for x
    x = 111,982.49/287.24
  6. Step 6: Final answer
    x = 389.85

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Why These Related Problems?

These problems maintain the same ratio (1.36) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.