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Finding the Fourth Proportional to 20.39, 28.14 and 12.62

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Solution

The fourth proportional to 20.39, 28.14 and 12.62 is: 17.42

Step by Step Solution

  1. Step 1: Write the proportion equation
    20.39 : 28.14 = 12.62 : x
  2. Step 2: Convert to fraction form
    20.39/28.14 = 12.62/x
  3. Step 3: Cross multiply
    20.39x = 28.14 × 12.62
  4. Step 4: Simplify right side
    20.39x = 355.16
  5. Step 5: Solve for x
    x = 355.16/20.39
  6. Step 6: Final answer
    x = 17.42

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.