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Finding the Fourth Proportional to 7.20, 10.81 and 5.39

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Solution

The fourth proportional to 7.20, 10.81 and 5.39 is: 8.09

Step by Step Solution

  1. Step 1: Write the proportion equation
    7.20 : 10.81 = 5.39 : x
  2. Step 2: Convert to fraction form
    7.20/10.81 = 5.39/x
  3. Step 3: Cross multiply
    7.20x = 10.81 × 5.39
  4. Step 4: Simplify right side
    7.20x = 58.27
  5. Step 5: Solve for x
    x = 58.27/7.20
  6. Step 6: Final answer
    x = 8.09

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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.