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Finding the Fourth Proportional to 639.83, 959.84 and 274.61

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Solution

The fourth proportional to 639.83, 959.84 and 274.61 is: 411.95

Step by Step Solution

  1. Step 1: Write the proportion equation
    639.83 : 959.84 = 274.61 : x
  2. Step 2: Convert to fraction form
    639.83/959.84 = 274.61/x
  3. Step 3: Cross multiply
    639.83x = 959.84 × 274.61
  4. Step 4: Simplify right side
    639.83x = 263,575.49
  5. Step 5: Solve for x
    x = 263,575.49/639.83
  6. Step 6: Final answer
    x = 411.95

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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.