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Finding the Fourth Proportional to 20.88, 31.31 and 8.04

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Solution

The fourth proportional to 20.88, 31.31 and 8.04 is: 12.05

Step by Step Solution

  1. Step 1: Write the proportion equation
    20.88 : 31.31 = 8.04 : x
  2. Step 2: Convert to fraction form
    20.88/31.31 = 8.04/x
  3. Step 3: Cross multiply
    20.88x = 31.31 × 8.04
  4. Step 4: Simplify right side
    20.88x = 251.69
  5. Step 5: Solve for x
    x = 251.69/20.88
  6. Step 6: Final answer
    x = 12.05

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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.