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Finding the Fourth Proportional to 138.71, 206.28 and 134.39

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Solution

The fourth proportional to 138.71, 206.28 and 134.39 is: 199.86

Step by Step Solution

  1. Step 1: Write the proportion equation
    138.71 : 206.28 = 134.39 : x
  2. Step 2: Convert to fraction form
    138.71/206.28 = 134.39/x
  3. Step 3: Cross multiply
    138.71x = 206.28 × 134.39
  4. Step 4: Simplify right side
    138.71x = 27,722.48
  5. Step 5: Solve for x
    x = 27,722.48/138.71
  6. Step 6: Final answer
    x = 199.86

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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.