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Finding the Fourth Proportional to 398.39, 549.17 and 280.00

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Solution

The fourth proportional to 398.39, 549.17 and 280.00 is: 385.97

Step by Step Solution

  1. Step 1: Write the proportion equation
    398.39 : 549.17 = 280.00 : x
  2. Step 2: Convert to fraction form
    398.39/549.17 = 280.00/x
  3. Step 3: Cross multiply
    398.39x = 549.17 × 280.00
  4. Step 4: Simplify right side
    398.39x = 153,764.85
  5. Step 5: Solve for x
    x = 153,764.85/398.39
  6. Step 6: Final answer
    x = 385.97

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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.