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Finding the Third Proportional to 9.81 and 21.31

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Solution

The third proportional to 9.81 and 21.31 is: 46.29

Step by Step Solution

  1. Step 1: Write the proportion equation
    9.81 : 21.31 = 21.31 : x
  2. Step 2: Convert to fraction form
    9.81/21.31 = 21.31/x
  3. Step 3: Cross multiply
    9.81x = 21.31 × 21.31
  4. Step 4: Simplify right side
    9.81x = 454.22
  5. Step 5: Solve for x
    x = 454.22/9.81
  6. Step 6: Final answer
    x = 46.29

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Why These Related Problems?

These problems maintain the same ratio (2.17) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.