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Finding the Fourth Proportional to 86.08, 128.76 and 68.08

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Solution

The fourth proportional to 86.08, 128.76 and 68.08 is: 101.84

Step by Step Solution

  1. Step 1: Write the proportion equation
    86.08 : 128.76 = 68.08 : x
  2. Step 2: Convert to fraction form
    86.08/128.76 = 68.08/x
  3. Step 3: Cross multiply
    86.08x = 128.76 × 68.08
  4. Step 4: Simplify right side
    86.08x = 8,765.98
  5. Step 5: Solve for x
    x = 8,765.98/86.08
  6. Step 6: Final answer
    x = 101.84

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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.