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Finding the Fourth Proportional to 481.13, 721.81 and 139.13

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Solution

The fourth proportional to 481.13, 721.81 and 139.13 is: 208.72

Step by Step Solution

  1. Step 1: Write the proportion equation
    481.13 : 721.81 = 139.13 : x
  2. Step 2: Convert to fraction form
    481.13/721.81 = 139.13/x
  3. Step 3: Cross multiply
    481.13x = 721.81 × 139.13
  4. Step 4: Simplify right side
    481.13x = 100,421.47
  5. Step 5: Solve for x
    x = 100,421.47/481.13
  6. Step 6: Final answer
    x = 208.72

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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.