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Finding the Fourth Proportional to 401.28, 601.92 and 205.72

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Solution

The fourth proportional to 401.28, 601.92 and 205.72 is: 308.58

Step by Step Solution

  1. Step 1: Write the proportion equation
    401.28 : 601.92 = 205.72 : x
  2. Step 2: Convert to fraction form
    401.28/601.92 = 205.72/x
  3. Step 3: Cross multiply
    401.28x = 601.92 × 205.72
  4. Step 4: Simplify right side
    401.28x = 123,825.95
  5. Step 5: Solve for x
    x = 123,825.95/401.28
  6. Step 6: Final answer
    x = 308.58

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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.