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Finding the Fourth Proportional to 496.89, 685.39 and 391.81

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Solution

The fourth proportional to 496.89, 685.39 and 391.81 is: 540.45

Step by Step Solution

  1. Step 1: Write the proportion equation
    496.89 : 685.39 = 391.81 : x
  2. Step 2: Convert to fraction form
    496.89/685.39 = 391.81/x
  3. Step 3: Cross multiply
    496.89x = 685.39 × 391.81
  4. Step 4: Simplify right side
    496.89x = 268,542.66
  5. Step 5: Solve for x
    x = 268,542.66/496.89
  6. Step 6: Final answer
    x = 540.45

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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.