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Finding the Third Proportional to 20.50 and 40.75

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Solution

The third proportional to 20.50 and 40.75 is: 81.00

Step by Step Solution

  1. Step 1: Write the proportion equation
    20.50 : 40.75 = 40.75 : x
  2. Step 2: Convert to fraction form
    20.50/40.75 = 40.75/x
  3. Step 3: Cross multiply
    20.50x = 40.75 × 40.75
  4. Step 4: Simplify right side
    20.50x = 1,660.56
  5. Step 5: Solve for x
    x = 1,660.56/20.50
  6. Step 6: Final answer
    x = 81.00

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Why These Related Problems?

These problems maintain the same ratio (1.99) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.