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Finding the Fourth Proportional to 138.28, 205.76 and 137.80

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Solution

The fourth proportional to 138.28, 205.76 and 137.80 is: 205.05

Step by Step Solution

  1. Step 1: Write the proportion equation
    138.28 : 205.76 = 137.80 : x
  2. Step 2: Convert to fraction form
    138.28/205.76 = 137.80/x
  3. Step 3: Cross multiply
    138.28x = 205.76 × 137.80
  4. Step 4: Simplify right side
    138.28x = 28,353.73
  5. Step 5: Solve for x
    x = 28,353.73/138.28
  6. Step 6: Final answer
    x = 205.05

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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.