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Finding the Fourth Proportional to 205.79, 308.69 and 84.09

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Solution

The fourth proportional to 205.79, 308.69 and 84.09 is: 126.14

Step by Step Solution

  1. Step 1: Write the proportion equation
    205.79 : 308.69 = 84.09 : x
  2. Step 2: Convert to fraction form
    205.79/308.69 = 84.09/x
  3. Step 3: Cross multiply
    205.79x = 308.69 × 84.09
  4. Step 4: Simplify right side
    205.79x = 25,957.74
  5. Step 5: Solve for x
    x = 25,957.74/205.79
  6. Step 6: Final answer
    x = 126.14

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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.