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Finding the Third Proportional to 621.74 and 685.34

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Solution

The third proportional to 621.74 and 685.34 is: 755.44

Step by Step Solution

  1. Step 1: Write the proportion equation
    621.74 : 685.34 = 685.34 : x
  2. Step 2: Convert to fraction form
    621.74/685.34 = 685.34/x
  3. Step 3: Cross multiply
    621.74x = 685.34 × 685.34
  4. Step 4: Simplify right side
    621.74x = 469,685.35
  5. Step 5: Solve for x
    x = 469,685.35/621.74
  6. Step 6: Final answer
    x = 755.44

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These problems maintain the same ratio (1.10) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.