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Finding the Third Proportional to 640.75 and 728.75

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Solution

The third proportional to 640.75 and 728.75 is: 828.84

Step by Step Solution

  1. Step 1: Write the proportion equation
    640.75 : 728.75 = 728.75 : x
  2. Step 2: Convert to fraction form
    640.75/728.75 = 728.75/x
  3. Step 3: Cross multiply
    640.75x = 728.75 × 728.75
  4. Step 4: Simplify right side
    640.75x = 531,076.56
  5. Step 5: Solve for x
    x = 531,076.56/640.75
  6. Step 6: Final answer
    x = 828.84

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