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Finding the Third Proportional to 21.21 and 30.85

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Solution

The third proportional to 21.21 and 30.85 is: 44.87

Step by Step Solution

  1. Step 1: Write the proportion equation
    21.21 : 30.85 = 30.85 : x
  2. Step 2: Convert to fraction form
    21.21/30.85 = 30.85/x
  3. Step 3: Cross multiply
    21.21x = 30.85 × 30.85
  4. Step 4: Simplify right side
    21.21x = 951.75
  5. Step 5: Solve for x
    x = 951.75/21.21
  6. Step 6: Final answer
    x = 44.87

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Why These Related Problems?

These problems maintain the same ratio (1.45) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.