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Finding the Third Proportional to 309.97 and 645.56

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Solution

The third proportional to 309.97 and 645.56 is: 1,344.48

Step by Step Solution

  1. Step 1: Write the proportion equation
    309.97 : 645.56 = 645.56 : x
  2. Step 2: Convert to fraction form
    309.97/645.56 = 645.56/x
  3. Step 3: Cross multiply
    309.97x = 645.56 × 645.56
  4. Step 4: Simplify right side
    309.97x = 416,750.94
  5. Step 5: Solve for x
    x = 416,750.94/309.97
  6. Step 6: Final answer
    x = 1,344.48

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Why These Related Problems?

These problems maintain the same ratio (2.08) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.