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Finding the Third Proportional to 619.31 and 821.81

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Solution

The third proportional to 619.31 and 821.81 is: 1,090.53

Step by Step Solution

  1. Step 1: Write the proportion equation
    619.31 : 821.81 = 821.81 : x
  2. Step 2: Convert to fraction form
    619.31/821.81 = 821.81/x
  3. Step 3: Cross multiply
    619.31x = 821.81 × 821.81
  4. Step 4: Simplify right side
    619.31x = 675,375.79
  5. Step 5: Solve for x
    x = 675,375.79/619.31
  6. Step 6: Final answer
    x = 1,090.53

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Why These Related Problems?

These problems maintain the same ratio (1.33) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.