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Finding the Fourth Proportional to 481.42, 721.45 and 220.78

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Solution

The fourth proportional to 481.42, 721.45 and 220.78 is: 330.86

Step by Step Solution

  1. Step 1: Write the proportion equation
    481.42 : 721.45 = 220.78 : x
  2. Step 2: Convert to fraction form
    481.42/721.45 = 220.78/x
  3. Step 3: Cross multiply
    481.42x = 721.45 × 220.78
  4. Step 4: Simplify right side
    481.42x = 159,281.73
  5. Step 5: Solve for x
    x = 159,281.73/481.42
  6. Step 6: Final answer
    x = 330.86

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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.