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Finding the Fourth Proportional to 490.75, 677.21 and 280.88

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Solution

The fourth proportional to 490.75, 677.21 and 280.88 is: 387.60

Step by Step Solution

  1. Step 1: Write the proportion equation
    490.75 : 677.21 = 280.88 : x
  2. Step 2: Convert to fraction form
    490.75/677.21 = 280.88/x
  3. Step 3: Cross multiply
    490.75x = 677.21 × 280.88
  4. Step 4: Simplify right side
    490.75x = 190,215.03
  5. Step 5: Solve for x
    x = 190,215.03/490.75
  6. Step 6: Final answer
    x = 387.60

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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.