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Finding the Fourth Proportional to 320.85, 481.14 and 138.15

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Solution

The fourth proportional to 320.85, 481.14 and 138.15 is: 207.17

Step by Step Solution

  1. Step 1: Write the proportion equation
    320.85 : 481.14 = 138.15 : x
  2. Step 2: Convert to fraction form
    320.85/481.14 = 138.15/x
  3. Step 3: Cross multiply
    320.85x = 481.14 × 138.15
  4. Step 4: Simplify right side
    320.85x = 66,469.49
  5. Step 5: Solve for x
    x = 66,469.49/320.85
  6. Step 6: Final answer
    x = 207.17

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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.