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Finding the Third Proportional to 680.91 and 778.78

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Solution

The third proportional to 680.91 and 778.78 is: 890.73

Step by Step Solution

  1. Step 1: Write the proportion equation
    680.91 : 778.78 = 778.78 : x
  2. Step 2: Convert to fraction form
    680.91/778.78 = 778.78/x
  3. Step 3: Cross multiply
    680.91x = 778.78 × 778.78
  4. Step 4: Simplify right side
    680.91x = 606,500.24
  5. Step 5: Solve for x
    x = 606,500.24/680.91
  6. Step 6: Final answer
    x = 890.73

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Why These Related Problems?

These problems maintain the same ratio (1.14) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.