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Finding the Fourth Proportional to 639.08, 958.60 and 422.60

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Solution

The fourth proportional to 639.08, 958.60 and 422.60 is: 633.89

Step by Step Solution

  1. Step 1: Write the proportion equation
    639.08 : 958.60 = 422.60 : x
  2. Step 2: Convert to fraction form
    639.08/958.60 = 422.60/x
  3. Step 3: Cross multiply
    639.08x = 958.60 × 422.60
  4. Step 4: Simplify right side
    639.08x = 405,104.36
  5. Step 5: Solve for x
    x = 405,104.36/639.08
  6. Step 6: Final answer
    x = 633.89

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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.