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Finding the Fourth Proportional to 490.58, 739.19 and 405.82

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Solution

The fourth proportional to 490.58, 739.19 and 405.82 is: 611.48

Step by Step Solution

  1. Step 1: Write the proportion equation
    490.58 : 739.19 = 405.82 : x
  2. Step 2: Convert to fraction form
    490.58/739.19 = 405.82/x
  3. Step 3: Cross multiply
    490.58x = 739.19 × 405.82
  4. Step 4: Simplify right side
    490.58x = 299,978.09
  5. Step 5: Solve for x
    x = 299,978.09/490.58
  6. Step 6: Final answer
    x = 611.48

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Why These Related Problems?

These problems maintain the same ratio (1.51) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.