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Finding the Fourth Proportional to 817.92, 1,229.31 and 720.72

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Solution

The fourth proportional to 817.92, 1,229.31 and 720.72 is: 1,083.22

Step by Step Solution

  1. Step 1: Write the proportion equation
    817.92 : 1,229.31 = 720.72 : x
  2. Step 2: Convert to fraction form
    817.92/1,229.31 = 720.72/x
  3. Step 3: Cross multiply
    817.92x = 1,229.31 × 720.72
  4. Step 4: Simplify right side
    817.92x = 885,988.30
  5. Step 5: Solve for x
    x = 885,988.30/817.92
  6. Step 6: Final answer
    x = 1,083.22

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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.