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Finding the Fourth Proportional to 136.71, 205.25 and 78.97

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Solution

The fourth proportional to 136.71, 205.25 and 78.97 is: 118.56

Step by Step Solution

  1. Step 1: Write the proportion equation
    136.71 : 205.25 = 78.97 : x
  2. Step 2: Convert to fraction form
    136.71/205.25 = 78.97/x
  3. Step 3: Cross multiply
    136.71x = 205.25 × 78.97
  4. Step 4: Simplify right side
    136.71x = 16,208.59
  5. Step 5: Solve for x
    x = 16,208.59/136.71
  6. Step 6: Final answer
    x = 118.56

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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.