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Finding the Fourth Proportional to 721, 1,081.45 and 310.14

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Solution

The fourth proportional to 721, 1,081.45 and 310.14 is: 465.19

Step by Step Solution

  1. Step 1: Write the proportion equation
    721 : 1,081.45 = 310.14 : x
  2. Step 2: Convert to fraction form
    721/1,081.45 = 310.14/x
  3. Step 3: Cross multiply
    721x = 1,081.45 × 310.14
  4. Step 4: Simplify right side
    721x = 335,400.90
  5. Step 5: Solve for x
    x = 335,400.90/721
  6. Step 6: Final answer
    x = 465.19

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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.