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Finding the Fourth Proportional to 86.82, 120.35 and 80.88

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Solution

The fourth proportional to 86.82, 120.35 and 80.88 is: 112.11

Step by Step Solution

  1. Step 1: Write the proportion equation
    86.82 : 120.35 = 80.88 : x
  2. Step 2: Convert to fraction form
    86.82/120.35 = 80.88/x
  3. Step 3: Cross multiply
    86.82x = 120.35 × 80.88
  4. Step 4: Simplify right side
    86.82x = 9,733.50
  5. Step 5: Solve for x
    x = 9,733.50/86.82
  6. Step 6: Final answer
    x = 112.11

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Why These Related Problems?

These problems maintain the same ratio (1.39) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.