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Finding the Fourth Proportional to 490.59, 677.03 and 280.78

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Solution

The fourth proportional to 490.59, 677.03 and 280.78 is: 387.48

Step by Step Solution

  1. Step 1: Write the proportion equation
    490.59 : 677.03 = 280.78 : x
  2. Step 2: Convert to fraction form
    490.59/677.03 = 280.78/x
  3. Step 3: Cross multiply
    490.59x = 677.03 × 280.78
  4. Step 4: Simplify right side
    490.59x = 190,093.39
  5. Step 5: Solve for x
    x = 190,093.39/490.59
  6. Step 6: Final answer
    x = 387.48

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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.