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Finding the Third Proportional to 18 and 21.13

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Solution

The third proportional to 18 and 21.13 is: 24.79

Step by Step Solution

  1. Step 1: Write the proportion equation
    18 : 21.13 = 21.13 : x
  2. Step 2: Convert to fraction form
    18/21.13 = 21.13/x
  3. Step 3: Cross multiply
    18x = 21.13 × 21.13
  4. Step 4: Simplify right side
    18x = 446.27
  5. Step 5: Solve for x
    x = 446.27/18
  6. Step 6: Final answer
    x = 24.79

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Why These Related Problems?

These problems maintain the same ratio (1.17) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.