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Finding the Fourth Proportional to 639.12, 958.68 and 422.04

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Solution

The fourth proportional to 639.12, 958.68 and 422.04 is: 633.06

Step by Step Solution

  1. Step 1: Write the proportion equation
    639.12 : 958.68 = 422.04 : x
  2. Step 2: Convert to fraction form
    639.12/958.68 = 422.04/x
  3. Step 3: Cross multiply
    639.12x = 958.68 × 422.04
  4. Step 4: Simplify right side
    639.12x = 404,601.31
  5. Step 5: Solve for x
    x = 404,601.31/639.12
  6. Step 6: Final answer
    x = 633.06

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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.