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Finding the Fourth Proportional to 138.10, 205.95 and 136.90

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Solution

The fourth proportional to 138.10, 205.95 and 136.90 is: 204.16

Step by Step Solution

  1. Step 1: Write the proportion equation
    138.10 : 205.95 = 136.90 : x
  2. Step 2: Convert to fraction form
    138.10/205.95 = 136.90/x
  3. Step 3: Cross multiply
    138.10x = 205.95 × 136.90
  4. Step 4: Simplify right side
    138.10x = 28,194.56
  5. Step 5: Solve for x
    x = 28,194.56/138.10
  6. Step 6: Final answer
    x = 204.16

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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.