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Finding the Fourth Proportional to 86.08, 118.13 and 85.69

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Solution

The fourth proportional to 86.08, 118.13 and 85.69 is: 117.59

Step by Step Solution

  1. Step 1: Write the proportion equation
    86.08 : 118.13 = 85.69 : x
  2. Step 2: Convert to fraction form
    86.08/118.13 = 85.69/x
  3. Step 3: Cross multiply
    86.08x = 118.13 × 85.69
  4. Step 4: Simplify right side
    86.08x = 10,122.56
  5. Step 5: Solve for x
    x = 10,122.56/86.08
  6. Step 6: Final answer
    x = 117.59

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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.