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Finding the Fourth Proportional to 401.38, 601.80 and 205.90

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Solution

The fourth proportional to 401.38, 601.80 and 205.90 is: 308.71

Step by Step Solution

  1. Step 1: Write the proportion equation
    401.38 : 601.80 = 205.90 : x
  2. Step 2: Convert to fraction form
    401.38/601.80 = 205.90/x
  3. Step 3: Cross multiply
    401.38x = 601.80 × 205.90
  4. Step 4: Simplify right side
    401.38x = 123,910.62
  5. Step 5: Solve for x
    x = 123,910.62/401.38
  6. Step 6: Final answer
    x = 308.71

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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.