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Finding the Fourth Proportional to 398.37, 548.39 and 342.78

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Solution

The fourth proportional to 398.37, 548.39 and 342.78 is: 471.87

Step by Step Solution

  1. Step 1: Write the proportion equation
    398.37 : 548.39 = 342.78 : x
  2. Step 2: Convert to fraction form
    398.37/548.39 = 342.78/x
  3. Step 3: Cross multiply
    398.37x = 548.39 × 342.78
  4. Step 4: Simplify right side
    398.37x = 187,977.98
  5. Step 5: Solve for x
    x = 187,977.98/398.37
  6. Step 6: Final answer
    x = 471.87

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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.