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Finding the Fourth Proportional to 138.10, 206.85 and 135.10

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Solution

The fourth proportional to 138.10, 206.85 and 135.10 is: 202.36

Step by Step Solution

  1. Step 1: Write the proportion equation
    138.10 : 206.85 = 135.10 : x
  2. Step 2: Convert to fraction form
    138.10/206.85 = 135.10/x
  3. Step 3: Cross multiply
    138.10x = 206.85 × 135.10
  4. Step 4: Simplify right side
    138.10x = 27,945.44
  5. Step 5: Solve for x
    x = 27,945.44/138.10
  6. Step 6: Final answer
    x = 202.36

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.