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Finding the Fourth Proportional to 489.28, 729.20 and 488.56

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Solution

The fourth proportional to 489.28, 729.20 and 488.56 is: 728.13

Step by Step Solution

  1. Step 1: Write the proportion equation
    489.28 : 729.20 = 488.56 : x
  2. Step 2: Convert to fraction form
    489.28/729.20 = 488.56/x
  3. Step 3: Cross multiply
    489.28x = 729.20 × 488.56
  4. Step 4: Simplify right side
    489.28x = 356,257.95
  5. Step 5: Solve for x
    x = 356,257.95/489.28
  6. Step 6: Final answer
    x = 728.13

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Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.