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Finding the Fourth Proportional to 642.31, 963.21 and 231.30

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Solution

The fourth proportional to 642.31, 963.21 and 231.30 is: 346.86

Step by Step Solution

  1. Step 1: Write the proportion equation
    642.31 : 963.21 = 231.30 : x
  2. Step 2: Convert to fraction form
    642.31/963.21 = 231.30/x
  3. Step 3: Cross multiply
    642.31x = 963.21 × 231.30
  4. Step 4: Simplify right side
    642.31x = 222,793.46
  5. Step 5: Solve for x
    x = 222,793.46/642.31
  6. Step 6: Final answer
    x = 346.86

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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.