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Finding the Fourth Proportional to 138.36, 206.39 and 135.80

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Solution

The fourth proportional to 138.36, 206.39 and 135.80 is: 202.57

Step by Step Solution

  1. Step 1: Write the proportion equation
    138.36 : 206.39 = 135.80 : x
  2. Step 2: Convert to fraction form
    138.36/206.39 = 135.80/x
  3. Step 3: Cross multiply
    138.36x = 206.39 × 135.80
  4. Step 4: Simplify right side
    138.36x = 28,027.76
  5. Step 5: Solve for x
    x = 28,027.76/138.36
  6. Step 6: Final answer
    x = 202.57

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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.