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Finding the Fourth Proportional to 8.71, 11.91 and 8.71

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Solution

The fourth proportional to 8.71, 11.91 and 8.71 is: 11.91

Step by Step Solution

  1. Step 1: Write the proportion equation
    8.71 : 11.91 = 8.71 : x
  2. Step 2: Convert to fraction form
    8.71/11.91 = 8.71/x
  3. Step 3: Cross multiply
    8.71x = 11.91 × 8.71
  4. Step 4: Simplify right side
    8.71x = 103.68
  5. Step 5: Solve for x
    x = 103.68/8.71
  6. Step 6: Final answer
    x = 11.91

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Why These Related Problems?

These problems maintain the same ratio (1.37) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.