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Finding the Fourth Proportional to 639.26, 958.97 and 206.45

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Solution

The fourth proportional to 639.26, 958.97 and 206.45 is: 309.70

Step by Step Solution

  1. Step 1: Write the proportion equation
    639.26 : 958.97 = 206.45 : x
  2. Step 2: Convert to fraction form
    639.26/958.97 = 206.45/x
  3. Step 3: Cross multiply
    639.26x = 958.97 × 206.45
  4. Step 4: Simplify right side
    639.26x = 197,979.36
  5. Step 5: Solve for x
    x = 197,979.36/639.26
  6. Step 6: Final answer
    x = 309.70

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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.