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Finding the Fourth Proportional to 490.28, 734.66 and 387.31

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Solution

The fourth proportional to 490.28, 734.66 and 387.31 is: 580.36

Step by Step Solution

  1. Step 1: Write the proportion equation
    490.28 : 734.66 = 387.31 : x
  2. Step 2: Convert to fraction form
    490.28/734.66 = 387.31/x
  3. Step 3: Cross multiply
    490.28x = 734.66 × 387.31
  4. Step 4: Simplify right side
    490.28x = 284,535.55
  5. Step 5: Solve for x
    x = 284,535.55/490.28
  6. Step 6: Final answer
    x = 580.36

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.