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Finding the Fourth Proportional to 206.08, 308.81 and 84.31

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Solution

The fourth proportional to 206.08, 308.81 and 84.31 is: 126.34

Step by Step Solution

  1. Step 1: Write the proportion equation
    206.08 : 308.81 = 84.31 : x
  2. Step 2: Convert to fraction form
    206.08/308.81 = 84.31/x
  3. Step 3: Cross multiply
    206.08x = 308.81 × 84.31
  4. Step 4: Simplify right side
    206.08x = 26,035.21
  5. Step 5: Solve for x
    x = 26,035.21/206.08
  6. Step 6: Final answer
    x = 126.34

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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.