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Finding the Fourth Proportional to 80.86, 111.53 and 79.66

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Solution

The fourth proportional to 80.86, 111.53 and 79.66 is: 109.87

Step by Step Solution

  1. Step 1: Write the proportion equation
    80.86 : 111.53 = 79.66 : x
  2. Step 2: Convert to fraction form
    80.86/111.53 = 79.66/x
  3. Step 3: Cross multiply
    80.86x = 111.53 × 79.66
  4. Step 4: Simplify right side
    80.86x = 8,884.48
  5. Step 5: Solve for x
    x = 8,884.48/80.86
  6. Step 6: Final answer
    x = 109.87

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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.