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Finding the Fourth Proportional to 397.45, 547.90 and 280.81

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Solution

The fourth proportional to 397.45, 547.90 and 280.81 is: 387.11

Step by Step Solution

  1. Step 1: Write the proportion equation
    397.45 : 547.90 = 280.81 : x
  2. Step 2: Convert to fraction form
    397.45/547.90 = 280.81/x
  3. Step 3: Cross multiply
    397.45x = 547.90 × 280.81
  4. Step 4: Simplify right side
    397.45x = 153,855.80
  5. Step 5: Solve for x
    x = 153,855.80/397.45
  6. Step 6: Final answer
    x = 387.11

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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.