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Finding the Fourth Proportional to 138.28, 208.52 and 136.45

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Solution

The fourth proportional to 138.28, 208.52 and 136.45 is: 205.76

Step by Step Solution

  1. Step 1: Write the proportion equation
    138.28 : 208.52 = 136.45 : x
  2. Step 2: Convert to fraction form
    138.28/208.52 = 136.45/x
  3. Step 3: Cross multiply
    138.28x = 208.52 × 136.45
  4. Step 4: Simplify right side
    138.28x = 28,452.55
  5. Step 5: Solve for x
    x = 28,452.55/138.28
  6. Step 6: Final answer
    x = 205.76

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Why These Related Problems?

These problems maintain the same ratio (1.51) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.