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Finding the Fourth Proportional to 86.86, 119.82 and 55.81

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Solution

The fourth proportional to 86.86, 119.82 and 55.81 is: 76.99

Step by Step Solution

  1. Step 1: Write the proportion equation
    86.86 : 119.82 = 55.81 : x
  2. Step 2: Convert to fraction form
    86.86/119.82 = 55.81/x
  3. Step 3: Cross multiply
    86.86x = 119.82 × 55.81
  4. Step 4: Simplify right side
    86.86x = 6,687.15
  5. Step 5: Solve for x
    x = 6,687.15/86.86
  6. Step 6: Final answer
    x = 76.99

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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.