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Finding the Fourth Proportional to 8.11, 12.09 and 7.22

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Solution

The fourth proportional to 8.11, 12.09 and 7.22 is: 10.75

Step by Step Solution

  1. Step 1: Write the proportion equation
    8.11 : 12.09 = 7.22 : x
  2. Step 2: Convert to fraction form
    8.11/12.09 = 7.22/x
  3. Step 3: Cross multiply
    8.11x = 12.09 × 7.22
  4. Step 4: Simplify right side
    8.11x = 87.24
  5. Step 5: Solve for x
    x = 87.24/8.11
  6. Step 6: Final answer
    x = 10.75

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Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.