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Finding the Fourth Proportional to 13.40, 20.06 and 12.61

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Solution

The fourth proportional to 13.40, 20.06 and 12.61 is: 18.88

Step by Step Solution

  1. Step 1: Write the proportion equation
    13.40 : 20.06 = 12.61 : x
  2. Step 2: Convert to fraction form
    13.40/20.06 = 12.61/x
  3. Step 3: Cross multiply
    13.40x = 20.06 × 12.61
  4. Step 4: Simplify right side
    13.40x = 252.96
  5. Step 5: Solve for x
    x = 252.96/13.40
  6. Step 6: Final answer
    x = 18.88

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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.