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Finding the Fourth Proportional to 481.20, 721.31 and 172.86

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Solution

The fourth proportional to 481.20, 721.31 and 172.86 is: 259.11

Step by Step Solution

  1. Step 1: Write the proportion equation
    481.20 : 721.31 = 172.86 : x
  2. Step 2: Convert to fraction form
    481.20/721.31 = 172.86/x
  3. Step 3: Cross multiply
    481.20x = 721.31 × 172.86
  4. Step 4: Simplify right side
    481.20x = 124,684.78
  5. Step 5: Solve for x
    x = 124,684.78/481.20
  6. Step 6: Final answer
    x = 259.11

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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.