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Finding the Fourth Proportional to 769.69, 1,062.39 and 489.79

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Solution

The fourth proportional to 769.69, 1,062.39 and 489.79 is: 676.05

Step by Step Solution

  1. Step 1: Write the proportion equation
    769.69 : 1,062.39 = 489.79 : x
  2. Step 2: Convert to fraction form
    769.69/1,062.39 = 489.79/x
  3. Step 3: Cross multiply
    769.69x = 1,062.39 × 489.79
  4. Step 4: Simplify right side
    769.69x = 520,348.00
  5. Step 5: Solve for x
    x = 520,348.00/769.69
  6. Step 6: Final answer
    x = 676.05

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.