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Finding the Third Proportional to 18.81 and 28.21

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Solution

The third proportional to 18.81 and 28.21 is: 42.31

Step by Step Solution

  1. Step 1: Write the proportion equation
    18.81 : 28.21 = 28.21 : x
  2. Step 2: Convert to fraction form
    18.81/28.21 = 28.21/x
  3. Step 3: Cross multiply
    18.81x = 28.21 × 28.21
  4. Step 4: Simplify right side
    18.81x = 795.78
  5. Step 5: Solve for x
    x = 795.78/18.81
  6. Step 6: Final answer
    x = 42.31

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.