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Finding the Fourth Proportional to 500.39, 689.14 and 489.63

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Solution

The fourth proportional to 500.39, 689.14 and 489.63 is: 674.31

Step by Step Solution

  1. Step 1: Write the proportion equation
    500.39 : 689.14 = 489.63 : x
  2. Step 2: Convert to fraction form
    500.39/689.14 = 489.63/x
  3. Step 3: Cross multiply
    500.39x = 689.14 × 489.63
  4. Step 4: Simplify right side
    500.39x = 337,422.94
  5. Step 5: Solve for x
    x = 337,422.94/500.39
  6. Step 6: Final answer
    x = 674.31

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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.