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Finding the Fourth Proportional to 397.28, 547.48 and 280.64

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Solution

The fourth proportional to 397.28, 547.48 and 280.64 is: 386.74

Step by Step Solution

  1. Step 1: Write the proportion equation
    397.28 : 547.48 = 280.64 : x
  2. Step 2: Convert to fraction form
    397.28/547.48 = 280.64/x
  3. Step 3: Cross multiply
    397.28x = 547.48 × 280.64
  4. Step 4: Simplify right side
    397.28x = 153,644.79
  5. Step 5: Solve for x
    x = 153,644.79/397.28
  6. Step 6: Final answer
    x = 386.74

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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.