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Finding the Fourth Proportional to 86.03, 128.78 and 68.03

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Solution

The fourth proportional to 86.03, 128.78 and 68.03 is: 101.83

Step by Step Solution

  1. Step 1: Write the proportion equation
    86.03 : 128.78 = 68.03 : x
  2. Step 2: Convert to fraction form
    86.03/128.78 = 68.03/x
  3. Step 3: Cross multiply
    86.03x = 128.78 × 68.03
  4. Step 4: Simplify right side
    86.03x = 8,760.56
  5. Step 5: Solve for x
    x = 8,760.56/86.03
  6. Step 6: Final answer
    x = 101.83

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