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Finding the Fourth Proportional to 490.61, 677.19 and 280.90

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Solution

The fourth proportional to 490.61, 677.19 and 280.90 is: 387.73

Step by Step Solution

  1. Step 1: Write the proportion equation
    490.61 : 677.19 = 280.90 : x
  2. Step 2: Convert to fraction form
    490.61/677.19 = 280.90/x
  3. Step 3: Cross multiply
    490.61x = 677.19 × 280.90
  4. Step 4: Simplify right side
    490.61x = 190,222.67
  5. Step 5: Solve for x
    x = 190,222.67/490.61
  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.