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Finding the Fourth Proportional to 8.86, 13.29 and 7.81

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Solution

The fourth proportional to 8.86, 13.29 and 7.81 is: 11.72

Step by Step Solution

  1. Step 1: Write the proportion equation
    8.86 : 13.29 = 7.81 : x
  2. Step 2: Convert to fraction form
    8.86/13.29 = 7.81/x
  3. Step 3: Cross multiply
    8.86x = 13.29 × 7.81
  4. Step 4: Simplify right side
    8.86x = 103.79
  5. Step 5: Solve for x
    x = 103.79/8.86
  6. Step 6: Final answer
    x = 11.72

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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.