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Finding the Fourth Proportional to 489.78, 734.74 and 215.87

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Solution

The fourth proportional to 489.78, 734.74 and 215.87 is: 323.83

Step by Step Solution

  1. Step 1: Write the proportion equation
    489.78 : 734.74 = 215.87 : x
  2. Step 2: Convert to fraction form
    489.78/734.74 = 215.87/x
  3. Step 3: Cross multiply
    489.78x = 734.74 × 215.87
  4. Step 4: Simplify right side
    489.78x = 158,604.11
  5. Step 5: Solve for x
    x = 158,604.11/489.78
  6. Step 6: Final answer
    x = 323.83

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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.