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Finding the Fourth Proportional to 138.40, 205.96 and 136.96

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Solution

The fourth proportional to 138.40, 205.96 and 136.96 is: 203.82

Step by Step Solution

  1. Step 1: Write the proportion equation
    138.40 : 205.96 = 136.96 : x
  2. Step 2: Convert to fraction form
    138.40/205.96 = 136.96/x
  3. Step 3: Cross multiply
    138.40x = 205.96 × 136.96
  4. Step 4: Simplify right side
    138.40x = 28,208.28
  5. Step 5: Solve for x
    x = 28,208.28/138.40
  6. Step 6: Final answer
    x = 203.82

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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.