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Finding the Fourth Proportional to 490.71, 677.11 and 280.90

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Solution

The fourth proportional to 490.71, 677.11 and 280.90 is: 387.60

Step by Step Solution

  1. Step 1: Write the proportion equation
    490.71 : 677.11 = 280.90 : x
  2. Step 2: Convert to fraction form
    490.71/677.11 = 280.90/x
  3. Step 3: Cross multiply
    490.71x = 677.11 × 280.90
  4. Step 4: Simplify right side
    490.71x = 190,200.20
  5. Step 5: Solve for x
    x = 190,200.20/490.71
  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.