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Finding the Fourth Proportional to 136.79, 204.67 and 81.74

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Solution

The fourth proportional to 136.79, 204.67 and 81.74 is: 122.31

Step by Step Solution

  1. Step 1: Write the proportion equation
    136.79 : 204.67 = 81.74 : x
  2. Step 2: Convert to fraction form
    136.79/204.67 = 81.74/x
  3. Step 3: Cross multiply
    136.79x = 204.67 × 81.74
  4. Step 4: Simplify right side
    136.79x = 16,730.34
  5. Step 5: Solve for x
    x = 16,730.34/136.79
  6. Step 6: Final answer
    x = 122.31

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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.