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Finding the Fourth Proportional to 649.09, 971.79 and 519.31

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Solution

The fourth proportional to 649.09, 971.79 and 519.31 is: 777.49

Step by Step Solution

  1. Step 1: Write the proportion equation
    649.09 : 971.79 = 519.31 : x
  2. Step 2: Convert to fraction form
    649.09/971.79 = 519.31/x
  3. Step 3: Cross multiply
    649.09x = 971.79 × 519.31
  4. Step 4: Simplify right side
    649.09x = 504,660.26
  5. Step 5: Solve for x
    x = 504,660.26/649.09
  6. Step 6: Final answer
    x = 777.49

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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.