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Finding the Fourth Proportional to 490.47, 676.81 and 288.65

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Solution

The fourth proportional to 490.47, 676.81 and 288.65 is: 398.31

Step by Step Solution

  1. Step 1: Write the proportion equation
    490.47 : 676.81 = 288.65 : x
  2. Step 2: Convert to fraction form
    490.47/676.81 = 288.65/x
  3. Step 3: Cross multiply
    490.47x = 676.81 × 288.65
  4. Step 4: Simplify right side
    490.47x = 195,361.21
  5. Step 5: Solve for x
    x = 195,361.21/490.47
  6. Step 6: Final answer
    x = 398.31

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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.