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Finding the Fourth Proportional to 138.38, 190.89 and 110.78

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Solution

The fourth proportional to 138.38, 190.89 and 110.78 is: 152.82

Step by Step Solution

  1. Step 1: Write the proportion equation
    138.38 : 190.89 = 110.78 : x
  2. Step 2: Convert to fraction form
    138.38/190.89 = 110.78/x
  3. Step 3: Cross multiply
    138.38x = 190.89 × 110.78
  4. Step 4: Simplify right side
    138.38x = 21,146.79
  5. Step 5: Solve for x
    x = 21,146.79/138.38
  6. Step 6: Final answer
    x = 152.82

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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.