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Finding the Fourth Proportional to 639.31, 958.96 and 206.77

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Solution

The fourth proportional to 639.31, 958.96 and 206.77 is: 310.15

Step by Step Solution

  1. Step 1: Write the proportion equation
    639.31 : 958.96 = 206.77 : x
  2. Step 2: Convert to fraction form
    639.31/958.96 = 206.77/x
  3. Step 3: Cross multiply
    639.31x = 958.96 × 206.77
  4. Step 4: Simplify right side
    639.31x = 198,279.36
  5. Step 5: Solve for x
    x = 198,279.36/639.31
  6. Step 6: Final answer
    x = 310.15

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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.