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Finding the Fourth Proportional to 639.90, 960.04 and 229.14

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Solution

The fourth proportional to 639.90, 960.04 and 229.14 is: 343.78

Step by Step Solution

  1. Step 1: Write the proportion equation
    639.90 : 960.04 = 229.14 : x
  2. Step 2: Convert to fraction form
    639.90/960.04 = 229.14/x
  3. Step 3: Cross multiply
    639.90x = 960.04 × 229.14
  4. Step 4: Simplify right side
    639.90x = 219,983.57
  5. Step 5: Solve for x
    x = 219,983.57/639.90
  6. Step 6: Final answer
    x = 343.78

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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.