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Finding the Fourth Proportional to 398.08, 548.79 and 279.85

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Solution

The fourth proportional to 398.08, 548.79 and 279.85 is: 385.80

Step by Step Solution

  1. Step 1: Write the proportion equation
    398.08 : 548.79 = 279.85 : x
  2. Step 2: Convert to fraction form
    398.08/548.79 = 279.85/x
  3. Step 3: Cross multiply
    398.08x = 548.79 × 279.85
  4. Step 4: Simplify right side
    398.08x = 153,578.88
  5. Step 5: Solve for x
    x = 153,578.88/398.08
  6. Step 6: Final answer
    x = 385.80

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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.