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Finding the Fourth Proportional to 206.25, 309.39 and 69.31

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Solution

The fourth proportional to 206.25, 309.39 and 69.31 is: 103.97

Step by Step Solution

  1. Step 1: Write the proportion equation
    206.25 : 309.39 = 69.31 : x
  2. Step 2: Convert to fraction form
    206.25/309.39 = 69.31/x
  3. Step 3: Cross multiply
    206.25x = 309.39 × 69.31
  4. Step 4: Simplify right side
    206.25x = 21,443.82
  5. Step 5: Solve for x
    x = 21,443.82/206.25
  6. Step 6: Final answer
    x = 103.97

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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.