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Finding the Fourth Proportional to 490.78, 677.26 and 269.72

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Solution

The fourth proportional to 490.78, 677.26 and 269.72 is: 372.20

Step by Step Solution

  1. Step 1: Write the proportion equation
    490.78 : 677.26 = 269.72 : x
  2. Step 2: Convert to fraction form
    490.78/677.26 = 269.72/x
  3. Step 3: Cross multiply
    490.78x = 677.26 × 269.72
  4. Step 4: Simplify right side
    490.78x = 182,670.57
  5. Step 5: Solve for x
    x = 182,670.57/490.78
  6. Step 6: Final answer
    x = 372.20

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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.