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Finding the Fourth Proportional to 639.96, 959.67 and 201.09

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Solution

The fourth proportional to 639.96, 959.67 and 201.09 is: 301.55

Step by Step Solution

  1. Step 1: Write the proportion equation
    639.96 : 959.67 = 201.09 : x
  2. Step 2: Convert to fraction form
    639.96/959.67 = 201.09/x
  3. Step 3: Cross multiply
    639.96x = 959.67 × 201.09
  4. Step 4: Simplify right side
    639.96x = 192,980.04
  5. Step 5: Solve for x
    x = 192,980.04/639.96
  6. Step 6: Final answer
    x = 301.55

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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.