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Finding the Fourth Proportional to 490.72, 677.54 and 397.88

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Solution

The fourth proportional to 490.72, 677.54 and 397.88 is: 549.36

Step by Step Solution

  1. Step 1: Write the proportion equation
    490.72 : 677.54 = 397.88 : x
  2. Step 2: Convert to fraction form
    490.72/677.54 = 397.88/x
  3. Step 3: Cross multiply
    490.72x = 677.54 × 397.88
  4. Step 4: Simplify right side
    490.72x = 269,579.62
  5. Step 5: Solve for x
    x = 269,579.62/490.72
  6. Step 6: Final answer
    x = 549.36

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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.