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Finding the Fourth Proportional to 138.66, 190.76 and 108.96

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Solution

The fourth proportional to 138.66, 190.76 and 108.96 is: 149.90

Step by Step Solution

  1. Step 1: Write the proportion equation
    138.66 : 190.76 = 108.96 : x
  2. Step 2: Convert to fraction form
    138.66/190.76 = 108.96/x
  3. Step 3: Cross multiply
    138.66x = 190.76 × 108.96
  4. Step 4: Simplify right side
    138.66x = 20,785.21
  5. Step 5: Solve for x
    x = 20,785.21/138.66
  6. Step 6: Final answer
    x = 149.90

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.