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Finding the Fourth Proportional to 136.82, 205.01 and 81.87

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Solution

The fourth proportional to 136.82, 205.01 and 81.87 is: 122.67

Step by Step Solution

  1. Step 1: Write the proportion equation
    136.82 : 205.01 = 81.87 : x
  2. Step 2: Convert to fraction form
    136.82/205.01 = 81.87/x
  3. Step 3: Cross multiply
    136.82x = 205.01 × 81.87
  4. Step 4: Simplify right side
    136.82x = 16,783.14
  5. Step 5: Solve for x
    x = 16,783.14/136.82
  6. Step 6: Final answer
    x = 122.67

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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.