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Finding the Fourth Proportional to 490.79, 677.30 and 280.95

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Solution

The fourth proportional to 490.79, 677.30 and 280.95 is: 387.71

Step by Step Solution

  1. Step 1: Write the proportion equation
    490.79 : 677.30 = 280.95 : x
  2. Step 2: Convert to fraction form
    490.79/677.30 = 280.95/x
  3. Step 3: Cross multiply
    490.79x = 677.30 × 280.95
  4. Step 4: Simplify right side
    490.79x = 190,287.30
  5. Step 5: Solve for x
    x = 190,287.30/490.79
  6. Step 6: Final answer
    x = 387.71

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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.