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Finding the Fourth Proportional to 640.78, 960.33 and 347.56

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Solution

The fourth proportional to 640.78, 960.33 and 347.56 is: 520.88

Step by Step Solution

  1. Step 1: Write the proportion equation
    640.78 : 960.33 = 347.56 : x
  2. Step 2: Convert to fraction form
    640.78/960.33 = 347.56/x
  3. Step 3: Cross multiply
    640.78x = 960.33 × 347.56
  4. Step 4: Simplify right side
    640.78x = 333,772.29
  5. Step 5: Solve for x
    x = 333,772.29/640.78
  6. Step 6: Final answer
    x = 520.88

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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.