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Finding the Fourth Proportional to 640.24, 959.82 and 255.28

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Solution

The fourth proportional to 640.24, 959.82 and 255.28 is: 382.70

Step by Step Solution

  1. Step 1: Write the proportion equation
    640.24 : 959.82 = 255.28 : x
  2. Step 2: Convert to fraction form
    640.24/959.82 = 255.28/x
  3. Step 3: Cross multiply
    640.24x = 959.82 × 255.28
  4. Step 4: Simplify right side
    640.24x = 245,022.85
  5. Step 5: Solve for x
    x = 245,022.85/640.24
  6. Step 6: Final answer
    x = 382.70

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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.