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Finding the Fourth Proportional to 490.50, 677.01 and 280.74

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Solution

The fourth proportional to 490.50, 677.01 and 280.74 is: 387.49

Step by Step Solution

  1. Step 1: Write the proportion equation
    490.50 : 677.01 = 280.74 : x
  2. Step 2: Convert to fraction form
    490.50/677.01 = 280.74/x
  3. Step 3: Cross multiply
    490.50x = 677.01 × 280.74
  4. Step 4: Simplify right side
    490.50x = 190,065.79
  5. Step 5: Solve for x
    x = 190,065.79/490.50
  6. Step 6: Final answer
    x = 387.49

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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.