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Finding the Fourth Proportional to 20.45, 30.69 and 10.82

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Solution

The fourth proportional to 20.45, 30.69 and 10.82 is: 16.23

Step by Step Solution

  1. Step 1: Write the proportion equation
    20.45 : 30.69 = 10.82 : x
  2. Step 2: Convert to fraction form
    20.45/30.69 = 10.82/x
  3. Step 3: Cross multiply
    20.45x = 30.69 × 10.82
  4. Step 4: Simplify right side
    20.45x = 331.93
  5. Step 5: Solve for x
    x = 331.93/20.45
  6. Step 6: Final answer
    x = 16.23

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.