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Finding the Fourth Proportional to 138.20, 205.80 and 134.60

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Solution

The fourth proportional to 138.20, 205.80 and 134.60 is: 200.44

Step by Step Solution

  1. Step 1: Write the proportion equation
    138.20 : 205.80 = 134.60 : x
  2. Step 2: Convert to fraction form
    138.20/205.80 = 134.60/x
  3. Step 3: Cross multiply
    138.20x = 205.80 × 134.60
  4. Step 4: Simplify right side
    138.20x = 27,700.68
  5. Step 5: Solve for x
    x = 27,700.68/138.20
  6. Step 6: Final answer
    x = 200.44

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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.