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Finding the Fourth Proportional to 639.40, 958.62 and 395.56

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Solution

The fourth proportional to 639.40, 958.62 and 395.56 is: 593.04

Step by Step Solution

  1. Step 1: Write the proportion equation
    639.40 : 958.62 = 395.56 : x
  2. Step 2: Convert to fraction form
    639.40/958.62 = 395.56/x
  3. Step 3: Cross multiply
    639.40x = 958.62 × 395.56
  4. Step 4: Simplify right side
    639.40x = 379,191.73
  5. Step 5: Solve for x
    x = 379,191.73/639.40
  6. Step 6: Final answer
    x = 593.04

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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.