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Finding the Fourth Proportional to 8.19, 11.31 and 6.39

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Solution

The fourth proportional to 8.19, 11.31 and 6.39 is: 8.82

Step by Step Solution

  1. Step 1: Write the proportion equation
    8.19 : 11.31 = 6.39 : x
  2. Step 2: Convert to fraction form
    8.19/11.31 = 6.39/x
  3. Step 3: Cross multiply
    8.19x = 11.31 × 6.39
  4. Step 4: Simplify right side
    8.19x = 72.21
  5. Step 5: Solve for x
    x = 72.21/8.19
  6. Step 6: Final answer
    x = 8.82

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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.