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Finding the Fourth Proportional to 86.11, 129.20 and 28.33

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Solution

The fourth proportional to 86.11, 129.20 and 28.33 is: 42.50

Step by Step Solution

  1. Step 1: Write the proportion equation
    86.11 : 129.20 = 28.33 : x
  2. Step 2: Convert to fraction form
    86.11/129.20 = 28.33/x
  3. Step 3: Cross multiply
    86.11x = 129.20 × 28.33
  4. Step 4: Simplify right side
    86.11x = 3,659.77
  5. Step 5: Solve for x
    x = 3,659.77/86.11
  6. Step 6: Final answer
    x = 42.50

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.