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Finding the Third Proportional to 20.50 and 21.81

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Solution

The third proportional to 20.50 and 21.81 is: 23.21

Step by Step Solution

  1. Step 1: Write the proportion equation
    20.50 : 21.81 = 21.81 : x
  2. Step 2: Convert to fraction form
    20.50/21.81 = 21.81/x
  3. Step 3: Cross multiply
    20.50x = 21.81 × 21.81
  4. Step 4: Simplify right side
    20.50x = 475.79
  5. Step 5: Solve for x
    x = 475.79/20.50
  6. Step 6: Final answer
    x = 23.21

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Why These Related Problems?

These problems maintain the same ratio (1.06) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.