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Finding the Fourth Proportional to 218.15, 327.05 and 81.12

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Solution

The fourth proportional to 218.15, 327.05 and 81.12 is: 121.61

Step by Step Solution

  1. Step 1: Write the proportion equation
    218.15 : 327.05 = 81.12 : x
  2. Step 2: Convert to fraction form
    218.15/327.05 = 81.12/x
  3. Step 3: Cross multiply
    218.15x = 327.05 × 81.12
  4. Step 4: Simplify right side
    218.15x = 26,530.30
  5. Step 5: Solve for x
    x = 26,530.30/218.15
  6. Step 6: Final answer
    x = 121.61

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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.