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Finding the Fourth Proportional to 256.38, 353.07 and 247.20

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Solution

The fourth proportional to 256.38, 353.07 and 247.20 is: 340.43

Step by Step Solution

  1. Step 1: Write the proportion equation
    256.38 : 353.07 = 247.20 : x
  2. Step 2: Convert to fraction form
    256.38/353.07 = 247.20/x
  3. Step 3: Cross multiply
    256.38x = 353.07 × 247.20
  4. Step 4: Simplify right side
    256.38x = 87,278.90
  5. Step 5: Solve for x
    x = 87,278.90/256.38
  6. Step 6: Final answer
    x = 340.43

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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.