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Finding the Fourth Proportional to 640.25, 960.20 and 229.31

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Solution

The fourth proportional to 640.25, 960.20 and 229.31 is: 343.90

Step by Step Solution

  1. Step 1: Write the proportion equation
    640.25 : 960.20 = 229.31 : x
  2. Step 2: Convert to fraction form
    640.25/960.20 = 229.31/x
  3. Step 3: Cross multiply
    640.25x = 960.20 × 229.31
  4. Step 4: Simplify right side
    640.25x = 220,181.63
  5. Step 5: Solve for x
    x = 220,181.63/640.25
  6. Step 6: Final answer
    x = 343.90

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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.