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Finding the Fourth Proportional to 86.05, 118.83 and 72.28

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Solution

The fourth proportional to 86.05, 118.83 and 72.28 is: 99.81

Step by Step Solution

  1. Step 1: Write the proportion equation
    86.05 : 118.83 = 72.28 : x
  2. Step 2: Convert to fraction form
    86.05/118.83 = 72.28/x
  3. Step 3: Cross multiply
    86.05x = 118.83 × 72.28
  4. Step 4: Simplify right side
    86.05x = 8,589.03
  5. Step 5: Solve for x
    x = 8,589.03/86.05
  6. Step 6: Final answer
    x = 99.81

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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.