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Finding the Fourth Proportional to 879.49, 1,318.20 and 489.30

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Solution

The fourth proportional to 879.49, 1,318.20 and 489.30 is: 733.37

Step by Step Solution

  1. Step 1: Write the proportion equation
    879.49 : 1,318.20 = 489.30 : x
  2. Step 2: Convert to fraction form
    879.49/1,318.20 = 489.30/x
  3. Step 3: Cross multiply
    879.49x = 1,318.20 × 489.30
  4. Step 4: Simplify right side
    879.49x = 644,995.26
  5. Step 5: Solve for x
    x = 644,995.26/879.49
  6. Step 6: Final answer
    x = 733.37

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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.