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Finding the Third Proportional to 407 and 631

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Solution

The third proportional to 407 and 631 is: 978.28

Step by Step Solution

  1. Step 1: Write the proportion equation
    407 : 631 = 631 : x
  2. Step 2: Convert to fraction form
    407/631 = 631/x
  3. Step 3: Cross multiply
    407x = 631 × 631
  4. Step 4: Simplify right side
    407x = 398,161
  5. Step 5: Solve for x
    x = 398,161/407
  6. Step 6: Final answer
    x = 978.28

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Why These Related Problems?

These problems maintain the same ratio (1.55) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.