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Finding the Fourth Proportional to 639.28, 959.40 and 254.56

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Solution

The fourth proportional to 639.28, 959.40 and 254.56 is: 382.03

Step by Step Solution

  1. Step 1: Write the proportion equation
    639.28 : 959.40 = 254.56 : x
  2. Step 2: Convert to fraction form
    639.28/959.40 = 254.56/x
  3. Step 3: Cross multiply
    639.28x = 959.40 × 254.56
  4. Step 4: Simplify right side
    639.28x = 244,224.86
  5. Step 5: Solve for x
    x = 244,224.86/639.28
  6. Step 6: Final answer
    x = 382.03

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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.