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Finding the Fourth Proportional to 490.57, 676.71 and 306.25

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Solution

The fourth proportional to 490.57, 676.71 and 306.25 is: 422.45

Step by Step Solution

  1. Step 1: Write the proportion equation
    490.57 : 676.71 = 306.25 : x
  2. Step 2: Convert to fraction form
    490.57/676.71 = 306.25/x
  3. Step 3: Cross multiply
    490.57x = 676.71 × 306.25
  4. Step 4: Simplify right side
    490.57x = 207,240.91
  5. Step 5: Solve for x
    x = 207,240.91/490.57
  6. Step 6: Final answer
    x = 422.45

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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.