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Finding the Third Proportional to 9.81 and 21.11

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Solution

The third proportional to 9.81 and 21.11 is: 45.44

Step by Step Solution

  1. Step 1: Write the proportion equation
    9.81 : 21.11 = 21.11 : x
  2. Step 2: Convert to fraction form
    9.81/21.11 = 21.11/x
  3. Step 3: Cross multiply
    9.81x = 21.11 × 21.11
  4. Step 4: Simplify right side
    9.81x = 445.69
  5. Step 5: Solve for x
    x = 445.69/9.81
  6. Step 6: Final answer
    x = 45.44

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Why These Related Problems?

These problems maintain the same ratio (2.15) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.