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Finding the Fourth Proportional to 108.60, 149.79 and 69.75

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Solution

The fourth proportional to 108.60, 149.79 and 69.75 is: 96.20

Step by Step Solution

  1. Step 1: Write the proportion equation
    108.60 : 149.79 = 69.75 : x
  2. Step 2: Convert to fraction form
    108.60/149.79 = 69.75/x
  3. Step 3: Cross multiply
    108.60x = 149.79 × 69.75
  4. Step 4: Simplify right side
    108.60x = 10,447.85
  5. Step 5: Solve for x
    x = 10,447.85/108.60
  6. Step 6: Final answer
    x = 96.20

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.