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Finding the Fourth Proportional to 640.35, 960.21 and 327.69

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Solution

The fourth proportional to 640.35, 960.21 and 327.69 is: 491.37

Step by Step Solution

  1. Step 1: Write the proportion equation
    640.35 : 960.21 = 327.69 : x
  2. Step 2: Convert to fraction form
    640.35/960.21 = 327.69/x
  3. Step 3: Cross multiply
    640.35x = 960.21 × 327.69
  4. Step 4: Simplify right side
    640.35x = 314,651.21
  5. Step 5: Solve for x
    x = 314,651.21/640.35
  6. Step 6: Final answer
    x = 491.37

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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.