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Finding the Fourth Proportional to 408.20, 612.38 and 119.66

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Solution

The fourth proportional to 408.20, 612.38 and 119.66 is: 179.51

Step by Step Solution

  1. Step 1: Write the proportion equation
    408.20 : 612.38 = 119.66 : x
  2. Step 2: Convert to fraction form
    408.20/612.38 = 119.66/x
  3. Step 3: Cross multiply
    408.20x = 612.38 × 119.66
  4. Step 4: Simplify right side
    408.20x = 73,277.39
  5. Step 5: Solve for x
    x = 73,277.39/408.20
  6. Step 6: Final answer
    x = 179.51

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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.