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Finding the Fourth Proportional to 640.75, 961.37 and 256.03

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Solution

The fourth proportional to 640.75, 961.37 and 256.03 is: 384.14

Step by Step Solution

  1. Step 1: Write the proportion equation
    640.75 : 961.37 = 256.03 : x
  2. Step 2: Convert to fraction form
    640.75/961.37 = 256.03/x
  3. Step 3: Cross multiply
    640.75x = 961.37 × 256.03
  4. Step 4: Simplify right side
    640.75x = 246,138.28
  5. Step 5: Solve for x
    x = 246,138.28/640.75
  6. Step 6: Final answer
    x = 384.14

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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.