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Finding the Fourth Proportional to 490.68, 677.21 and 280.94

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Solution

The fourth proportional to 490.68, 677.21 and 280.94 is: 387.73

Step by Step Solution

  1. Step 1: Write the proportion equation
    490.68 : 677.21 = 280.94 : x
  2. Step 2: Convert to fraction form
    490.68/677.21 = 280.94/x
  3. Step 3: Cross multiply
    490.68x = 677.21 × 280.94
  4. Step 4: Simplify right side
    490.68x = 190,250.59
  5. Step 5: Solve for x
    x = 190,250.59/490.68
  6. Step 6: Final answer
    x = 387.73

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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.