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Finding the Fourth Proportional to 398.27, 549.38 and 280.42

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Solution

The fourth proportional to 398.27, 549.38 and 280.42 is: 386.81

Step by Step Solution

  1. Step 1: Write the proportion equation
    398.27 : 549.38 = 280.42 : x
  2. Step 2: Convert to fraction form
    398.27/549.38 = 280.42/x
  3. Step 3: Cross multiply
    398.27x = 549.38 × 280.42
  4. Step 4: Simplify right side
    398.27x = 154,056.99
  5. Step 5: Solve for x
    x = 154,056.99/398.27
  6. Step 6: Final answer
    x = 386.81

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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.