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Finding the Fourth Proportional to 205.62, 308.57 and 82.21

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Solution

The fourth proportional to 205.62, 308.57 and 82.21 is: 123.37

Step by Step Solution

  1. Step 1: Write the proportion equation
    205.62 : 308.57 = 82.21 : x
  2. Step 2: Convert to fraction form
    205.62/308.57 = 82.21/x
  3. Step 3: Cross multiply
    205.62x = 308.57 × 82.21
  4. Step 4: Simplify right side
    205.62x = 25,367.80
  5. Step 5: Solve for x
    x = 25,367.80/205.62
  6. Step 6: Final answer
    x = 123.37

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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.