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Finding the Fourth Proportional to 639.00, 956.97 and 394.78

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Solution

The fourth proportional to 639.00, 956.97 and 394.78 is: 591.23

Step by Step Solution

  1. Step 1: Write the proportion equation
    639.00 : 956.97 = 394.78 : x
  2. Step 2: Convert to fraction form
    639.00/956.97 = 394.78/x
  3. Step 3: Cross multiply
    639.00x = 956.97 × 394.78
  4. Step 4: Simplify right side
    639.00x = 377,792.62
  5. Step 5: Solve for x
    x = 377,792.62/639.00
  6. Step 6: Final answer
    x = 591.23

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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.