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Finding the Fourth Proportional to 639.36, 959.01 and 206.49

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Solution

The fourth proportional to 639.36, 959.01 and 206.49 is: 309.73

Step by Step Solution

  1. Step 1: Write the proportion equation
    639.36 : 959.01 = 206.49 : x
  2. Step 2: Convert to fraction form
    639.36/959.01 = 206.49/x
  3. Step 3: Cross multiply
    639.36x = 959.01 × 206.49
  4. Step 4: Simplify right side
    639.36x = 198,025.97
  5. Step 5: Solve for x
    x = 198,025.97/639.36
  6. Step 6: Final answer
    x = 309.73

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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.