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Finding the Fourth Proportional to 721.30, 1,081.22 and 281.94

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Solution

The fourth proportional to 721.30, 1,081.22 and 281.94 is: 422.63

Step by Step Solution

  1. Step 1: Write the proportion equation
    721.30 : 1,081.22 = 281.94 : x
  2. Step 2: Convert to fraction form
    721.30/1,081.22 = 281.94/x
  3. Step 3: Cross multiply
    721.30x = 1,081.22 × 281.94
  4. Step 4: Simplify right side
    721.30x = 304,843.68
  5. Step 5: Solve for x
    x = 304,843.68/721.30
  6. Step 6: Final answer
    x = 422.63

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.