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Finding the Fourth Proportional to 109.30, 149.81 and 107.78

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Solution

The fourth proportional to 109.30, 149.81 and 107.78 is: 147.74

Step by Step Solution

  1. Step 1: Write the proportion equation
    109.30 : 149.81 = 107.78 : x
  2. Step 2: Convert to fraction form
    109.30/149.81 = 107.78/x
  3. Step 3: Cross multiply
    109.30x = 149.81 × 107.78
  4. Step 4: Simplify right side
    109.30x = 16,147.17
  5. Step 5: Solve for x
    x = 16,147.17/109.30
  6. Step 6: Final answer
    x = 147.74

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Why These Related Problems?

These problems maintain the same ratio (1.37) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.