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Finding the Fourth Proportional to 489.20, 733.48 and 215.28

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Solution

The fourth proportional to 489.20, 733.48 and 215.28 is: 322.78

Step by Step Solution

  1. Step 1: Write the proportion equation
    489.20 : 733.48 = 215.28 : x
  2. Step 2: Convert to fraction form
    489.20/733.48 = 215.28/x
  3. Step 3: Cross multiply
    489.20x = 733.48 × 215.28
  4. Step 4: Simplify right side
    489.20x = 157,903.57
  5. Step 5: Solve for x
    x = 157,903.57/489.20
  6. Step 6: Final answer
    x = 322.78

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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.