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Finding the Fourth Proportional to 398.14, 549.11 and 280.51

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Solution

The fourth proportional to 398.14, 549.11 and 280.51 is: 386.87

Step by Step Solution

  1. Step 1: Write the proportion equation
    398.14 : 549.11 = 280.51 : x
  2. Step 2: Convert to fraction form
    398.14/549.11 = 280.51/x
  3. Step 3: Cross multiply
    398.14x = 549.11 × 280.51
  4. Step 4: Simplify right side
    398.14x = 154,029.47
  5. Step 5: Solve for x
    x = 154,029.47/398.14
  6. Step 6: Final answer
    x = 386.87

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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.