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Finding the Third Proportional to 639 and 710

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Solution

The third proportional to 639 and 710 is: 788.89

Step by Step Solution

  1. Step 1: Write the proportion equation
    639 : 710 = 710 : x
  2. Step 2: Convert to fraction form
    639/710 = 710/x
  3. Step 3: Cross multiply
    639x = 710 × 710
  4. Step 4: Simplify right side
    639x = 504,100
  5. Step 5: Solve for x
    x = 504,100/639
  6. Step 6: Final answer
    x = 788.89

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Why These Related Problems?

These problems maintain the same ratio (1.11) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.