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Finding the Fourth Proportional to 641.96, 963.06 and 489.78

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Solution

The fourth proportional to 641.96, 963.06 and 489.78 is: 734.76

Step by Step Solution

  1. Step 1: Write the proportion equation
    641.96 : 963.06 = 489.78 : x
  2. Step 2: Convert to fraction form
    641.96/963.06 = 489.78/x
  3. Step 3: Cross multiply
    641.96x = 963.06 × 489.78
  4. Step 4: Simplify right side
    641.96x = 471,685.69
  5. Step 5: Solve for x
    x = 471,685.69/641.96
  6. Step 6: Final answer
    x = 734.76

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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.