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Finding the Fourth Proportional to 108.20, 163.11 and 103.40

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Solution

The fourth proportional to 108.20, 163.11 and 103.40 is: 155.87

Step by Step Solution

  1. Step 1: Write the proportion equation
    108.20 : 163.11 = 103.40 : x
  2. Step 2: Convert to fraction form
    108.20/163.11 = 103.40/x
  3. Step 3: Cross multiply
    108.20x = 163.11 × 103.40
  4. Step 4: Simplify right side
    108.20x = 16,865.57
  5. Step 5: Solve for x
    x = 16,865.57/108.20
  6. Step 6: Final answer
    x = 155.87

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Why These Related Problems?

These problems maintain the same ratio (1.51) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.