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Finding the Fourth Proportional to 205.38, 307.80 and 83.61

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Solution

The fourth proportional to 205.38, 307.80 and 83.61 is: 125.31

Step by Step Solution

  1. Step 1: Write the proportion equation
    205.38 : 307.80 = 83.61 : x
  2. Step 2: Convert to fraction form
    205.38/307.80 = 83.61/x
  3. Step 3: Cross multiply
    205.38x = 307.80 × 83.61
  4. Step 4: Simplify right side
    205.38x = 25,735.16
  5. Step 5: Solve for x
    x = 25,735.16/205.38
  6. Step 6: Final answer
    x = 125.31

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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.