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Finding the Fourth Proportional to 387.28, 579.86 and 256.97

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Solution

The fourth proportional to 387.28, 579.86 and 256.97 is: 384.75

Step by Step Solution

  1. Step 1: Write the proportion equation
    387.28 : 579.86 = 256.97 : x
  2. Step 2: Convert to fraction form
    387.28/579.86 = 256.97/x
  3. Step 3: Cross multiply
    387.28x = 579.86 × 256.97
  4. Step 4: Simplify right side
    387.28x = 149,007.75
  5. Step 5: Solve for x
    x = 149,007.75/387.28
  6. Step 6: Final answer
    x = 384.75

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.