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Finding the Fourth Proportional to 108.86, 163.13 and 85.95

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Solution

The fourth proportional to 108.86, 163.13 and 85.95 is: 128.80

Step by Step Solution

  1. Step 1: Write the proportion equation
    108.86 : 163.13 = 85.95 : x
  2. Step 2: Convert to fraction form
    108.86/163.13 = 85.95/x
  3. Step 3: Cross multiply
    108.86x = 163.13 × 85.95
  4. Step 4: Simplify right side
    108.86x = 14,020.59
  5. Step 5: Solve for x
    x = 14,020.59/108.86
  6. Step 6: Final answer
    x = 128.80

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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.