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Finding the Fourth Proportional to 320.70, 481.22 and 138.09

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Solution

The fourth proportional to 320.70, 481.22 and 138.09 is: 207.21

Step by Step Solution

  1. Step 1: Write the proportion equation
    320.70 : 481.22 = 138.09 : x
  2. Step 2: Convert to fraction form
    320.70/481.22 = 138.09/x
  3. Step 3: Cross multiply
    320.70x = 481.22 × 138.09
  4. Step 4: Simplify right side
    320.70x = 66,451.67
  5. Step 5: Solve for x
    x = 66,451.67/320.70
  6. Step 6: Final answer
    x = 207.21

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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.