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Finding the Fourth Proportional to 490.20, 676.45 and 315.64

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Solution

The fourth proportional to 490.20, 676.45 and 315.64 is: 435.57

Step by Step Solution

  1. Step 1: Write the proportion equation
    490.20 : 676.45 = 315.64 : x
  2. Step 2: Convert to fraction form
    490.20/676.45 = 315.64/x
  3. Step 3: Cross multiply
    490.20x = 676.45 × 315.64
  4. Step 4: Simplify right side
    490.20x = 213,514.68
  5. Step 5: Solve for x
    x = 213,514.68/490.20
  6. Step 6: Final answer
    x = 435.57

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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.