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Finding the Fourth Proportional to 640.28, 960.56 and 207.44

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Solution

The fourth proportional to 640.28, 960.56 and 207.44 is: 311.21

Step by Step Solution

  1. Step 1: Write the proportion equation
    640.28 : 960.56 = 207.44 : x
  2. Step 2: Convert to fraction form
    640.28/960.56 = 207.44/x
  3. Step 3: Cross multiply
    640.28x = 960.56 × 207.44
  4. Step 4: Simplify right side
    640.28x = 199,258.57
  5. Step 5: Solve for x
    x = 199,258.57/640.28
  6. Step 6: Final answer
    x = 311.21

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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.