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Finding the Fourth Proportional to 489.30, 734.31 and 324.78

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Solution

The fourth proportional to 489.30, 734.31 and 324.78 is: 487.41

Step by Step Solution

  1. Step 1: Write the proportion equation
    489.30 : 734.31 = 324.78 : x
  2. Step 2: Convert to fraction form
    489.30/734.31 = 324.78/x
  3. Step 3: Cross multiply
    489.30x = 734.31 × 324.78
  4. Step 4: Simplify right side
    489.30x = 238,489.20
  5. Step 5: Solve for x
    x = 238,489.20/489.30
  6. Step 6: Final answer
    x = 487.41

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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.