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Finding the Third Proportional to 15.71 and 20.79

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Solution

The third proportional to 15.71 and 20.79 is: 27.52

Step by Step Solution

  1. Step 1: Write the proportion equation
    15.71 : 20.79 = 20.79 : x
  2. Step 2: Convert to fraction form
    15.71/20.79 = 20.79/x
  3. Step 3: Cross multiply
    15.71x = 20.79 × 20.79
  4. Step 4: Simplify right side
    15.71x = 432.35
  5. Step 5: Solve for x
    x = 432.35/15.71
  6. Step 6: Final answer
    x = 27.52

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Why These Related Problems?

These problems maintain the same ratio (1.32) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.