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Finding the Fourth Proportional to 640.44, 960.80 and 207.63

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Solution

The fourth proportional to 640.44, 960.80 and 207.63 is: 311.49

Step by Step Solution

  1. Step 1: Write the proportion equation
    640.44 : 960.80 = 207.63 : x
  2. Step 2: Convert to fraction form
    640.44/960.80 = 207.63/x
  3. Step 3: Cross multiply
    640.44x = 960.80 × 207.63
  4. Step 4: Simplify right side
    640.44x = 199,489.87
  5. Step 5: Solve for x
    x = 199,489.87/640.44
  6. Step 6: Final answer
    x = 311.49

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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.