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Finding the Fourth Proportional to 206.05, 308.79 and 84.19

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Solution

The fourth proportional to 206.05, 308.79 and 84.19 is: 126.17

Step by Step Solution

  1. Step 1: Write the proportion equation
    206.05 : 308.79 = 84.19 : x
  2. Step 2: Convert to fraction form
    206.05/308.79 = 84.19/x
  3. Step 3: Cross multiply
    206.05x = 308.79 × 84.19
  4. Step 4: Simplify right side
    206.05x = 25,997.03
  5. Step 5: Solve for x
    x = 25,997.03/206.05
  6. Step 6: Final answer
    x = 126.17

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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.