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Finding the Third Proportional to 521 and 631

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Solution

The third proportional to 521 and 631 is: 764.22

Step by Step Solution

  1. Step 1: Write the proportion equation
    521 : 631 = 631 : x
  2. Step 2: Convert to fraction form
    521/631 = 631/x
  3. Step 3: Cross multiply
    521x = 631 × 631
  4. Step 4: Simplify right side
    521x = 398,161
  5. Step 5: Solve for x
    x = 398,161/521
  6. Step 6: Final answer
    x = 764.22

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Why These Related Problems?

These problems maintain the same ratio (1.21) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.