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Finding the Third Proportional to 69.19 and 138.38

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Solution

The third proportional to 69.19 and 138.38 is: 276.75

Step by Step Solution

  1. Step 1: Write the proportion equation
    69.19 : 138.38 = 138.38 : x
  2. Step 2: Convert to fraction form
    69.19/138.38 = 138.38/x
  3. Step 3: Cross multiply
    69.19x = 138.38 × 138.38
  4. Step 4: Simplify right side
    69.19x = 19,147.64
  5. Step 5: Solve for x
    x = 19,147.64/69.19
  6. Step 6: Final answer
    x = 276.75

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Why These Related Problems?

These problems maintain the same ratio (2) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.