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Finding the Fourth Proportional to 205.85, 308.79 and 68.91

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Solution

The fourth proportional to 205.85, 308.79 and 68.91 is: 103.37

Step by Step Solution

  1. Step 1: Write the proportion equation
    205.85 : 308.79 = 68.91 : x
  2. Step 2: Convert to fraction form
    205.85/308.79 = 68.91/x
  3. Step 3: Cross multiply
    205.85x = 308.79 × 68.91
  4. Step 4: Simplify right side
    205.85x = 21,278.72
  5. Step 5: Solve for x
    x = 21,278.72/205.85
  6. Step 6: Final answer
    x = 103.37

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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.