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Finding the Third Proportional to 12.75 and 20

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Solution

The third proportional to 12.75 and 20 is: 31.37

Step by Step Solution

  1. Step 1: Write the proportion equation
    12.75 : 20 = 20 : x
  2. Step 2: Convert to fraction form
    12.75/20 = 20/x
  3. Step 3: Cross multiply
    12.75x = 20 × 20
  4. Step 4: Simplify right side
    12.75x = 400
  5. Step 5: Solve for x
    x = 400/12.75
  6. Step 6: Final answer
    x = 31.37

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Why These Related Problems?

These problems maintain the same ratio (1.57) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.