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Finding the Fourth Proportional to 639.75, 959.87 and 255.03

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Solution

The fourth proportional to 639.75, 959.87 and 255.03 is: 382.64

Step by Step Solution

  1. Step 1: Write the proportion equation
    639.75 : 959.87 = 255.03 : x
  2. Step 2: Convert to fraction form
    639.75/959.87 = 255.03/x
  3. Step 3: Cross multiply
    639.75x = 959.87 × 255.03
  4. Step 4: Simplify right side
    639.75x = 244,794.37
  5. Step 5: Solve for x
    x = 244,794.37/639.75
  6. Step 6: Final answer
    x = 382.64

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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.