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Finding the Fourth Proportional to 138.46, 207.78 and 97.78

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Solution

The fourth proportional to 138.46, 207.78 and 97.78 is: 146.73

Step by Step Solution

  1. Step 1: Write the proportion equation
    138.46 : 207.78 = 97.78 : x
  2. Step 2: Convert to fraction form
    138.46/207.78 = 97.78/x
  3. Step 3: Cross multiply
    138.46x = 207.78 × 97.78
  4. Step 4: Simplify right side
    138.46x = 20,316.73
  5. Step 5: Solve for x
    x = 20,316.73/138.46
  6. Step 6: Final answer
    x = 146.73

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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.