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Finding the Fourth Proportional to 138.06, 205.38 and 137.79

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Solution

The fourth proportional to 138.06, 205.38 and 137.79 is: 204.98

Step by Step Solution

  1. Step 1: Write the proportion equation
    138.06 : 205.38 = 137.79 : x
  2. Step 2: Convert to fraction form
    138.06/205.38 = 137.79/x
  3. Step 3: Cross multiply
    138.06x = 205.38 × 137.79
  4. Step 4: Simplify right side
    138.06x = 28,299.31
  5. Step 5: Solve for x
    x = 28,299.31/138.06
  6. Step 6: Final answer
    x = 204.98

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Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.