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Finding the Fourth Proportional to 642.38, 963.58 and 203.61

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Solution

The fourth proportional to 642.38, 963.58 and 203.61 is: 305.43

Step by Step Solution

  1. Step 1: Write the proportion equation
    642.38 : 963.58 = 203.61 : x
  2. Step 2: Convert to fraction form
    642.38/963.58 = 203.61/x
  3. Step 3: Cross multiply
    642.38x = 963.58 × 203.61
  4. Step 4: Simplify right side
    642.38x = 196,198.01
  5. Step 5: Solve for x
    x = 196,198.01/642.38
  6. Step 6: Final answer
    x = 305.43

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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.