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Finding the Third Proportional to 13.80 and 20.20

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Solution

The third proportional to 13.80 and 20.20 is: 29.56

Step by Step Solution

  1. Step 1: Write the proportion equation
    13.80 : 20.20 = 20.20 : x
  2. Step 2: Convert to fraction form
    13.80/20.20 = 20.20/x
  3. Step 3: Cross multiply
    13.80x = 20.20 × 20.20
  4. Step 4: Simplify right side
    13.80x = 407.85
  5. Step 5: Solve for x
    x = 407.85/13.80
  6. Step 6: Final answer
    x = 29.56

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Why These Related Problems?

These problems maintain the same ratio (1.46) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.