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Finding the Fourth Proportional to 81.42, 122.13 and 27.30

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Solution

The fourth proportional to 81.42, 122.13 and 27.30 is: 40.95

Step by Step Solution

  1. Step 1: Write the proportion equation
    81.42 : 122.13 = 27.30 : x
  2. Step 2: Convert to fraction form
    81.42/122.13 = 27.30/x
  3. Step 3: Cross multiply
    81.42x = 122.13 × 27.30
  4. Step 4: Simplify right side
    81.42x = 3,334.15
  5. Step 5: Solve for x
    x = 3,334.15/81.42
  6. Step 6: Final answer
    x = 40.95

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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.