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Finding the Fourth Proportional to 489.67, 729.79 and 488.90

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Solution

The fourth proportional to 489.67, 729.79 and 488.90 is: 728.65

Step by Step Solution

  1. Step 1: Write the proportion equation
    489.67 : 729.79 = 488.90 : x
  2. Step 2: Convert to fraction form
    489.67/729.79 = 488.90/x
  3. Step 3: Cross multiply
    489.67x = 729.79 × 488.90
  4. Step 4: Simplify right side
    489.67x = 356,794.93
  5. Step 5: Solve for x
    x = 356,794.93/489.67
  6. Step 6: Final answer
    x = 728.65

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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.