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Finding the Fourth Proportional to 490.78, 676.92 and 315.82

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Solution

The fourth proportional to 490.78, 676.92 and 315.82 is: 435.60

Step by Step Solution

  1. Step 1: Write the proportion equation
    490.78 : 676.92 = 315.82 : x
  2. Step 2: Convert to fraction form
    490.78/676.92 = 315.82/x
  3. Step 3: Cross multiply
    490.78x = 676.92 × 315.82
  4. Step 4: Simplify right side
    490.78x = 213,784.87
  5. Step 5: Solve for x
    x = 213,784.87/490.78
  6. Step 6: Final answer
    x = 435.60

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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.