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Finding the Fourth Proportional to 20.29, 28.01 and 13.28

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Solution

The fourth proportional to 20.29, 28.01 and 13.28 is: 18.34

Step by Step Solution

  1. Step 1: Write the proportion equation
    20.29 : 28.01 = 13.28 : x
  2. Step 2: Convert to fraction form
    20.29/28.01 = 13.28/x
  3. Step 3: Cross multiply
    20.29x = 28.01 × 13.28
  4. Step 4: Simplify right side
    20.29x = 371.98
  5. Step 5: Solve for x
    x = 371.98/20.29
  6. Step 6: Final answer
    x = 18.34

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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.