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Finding the Fourth Proportional to 398.80, 550.47 and 251.47

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Solution

The fourth proportional to 398.80, 550.47 and 251.47 is: 347.11

Step by Step Solution

  1. Step 1: Write the proportion equation
    398.80 : 550.47 = 251.47 : x
  2. Step 2: Convert to fraction form
    398.80/550.47 = 251.47/x
  3. Step 3: Cross multiply
    398.80x = 550.47 × 251.47
  4. Step 4: Simplify right side
    398.80x = 138,426.69
  5. Step 5: Solve for x
    x = 138,426.69/398.80
  6. Step 6: Final answer
    x = 347.11

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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.