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Finding the Third Proportional to 138.38 and 299.81

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Solution

The third proportional to 138.38 and 299.81 is: 649.59

Step by Step Solution

  1. Step 1: Write the proportion equation
    138.38 : 299.81 = 299.81 : x
  2. Step 2: Convert to fraction form
    138.38/299.81 = 299.81/x
  3. Step 3: Cross multiply
    138.38x = 299.81 × 299.81
  4. Step 4: Simplify right side
    138.38x = 89,887.54
  5. Step 5: Solve for x
    x = 89,887.54/138.38
  6. Step 6: Final answer
    x = 649.59

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Why These Related Problems?

These problems maintain the same ratio (2.17) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.