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Finding the Fourth Proportional to 638.80, 958.35 and 205.96

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Solution

The fourth proportional to 638.80, 958.35 and 205.96 is: 308.99

Step by Step Solution

  1. Step 1: Write the proportion equation
    638.80 : 958.35 = 205.96 : x
  2. Step 2: Convert to fraction form
    638.80/958.35 = 205.96/x
  3. Step 3: Cross multiply
    638.80x = 958.35 × 205.96
  4. Step 4: Simplify right side
    638.80x = 197,381.77
  5. Step 5: Solve for x
    x = 197,381.77/638.80
  6. Step 6: Final answer
    x = 308.99

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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.