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Finding the Fourth Proportional to 639.86, 959.59 and 274.42

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Solution

The fourth proportional to 639.86, 959.59 and 274.42 is: 411.53

Step by Step Solution

  1. Step 1: Write the proportion equation
    639.86 : 959.59 = 274.42 : x
  2. Step 2: Convert to fraction form
    639.86/959.59 = 274.42/x
  3. Step 3: Cross multiply
    639.86x = 959.59 × 274.42
  4. Step 4: Simplify right side
    639.86x = 263,324.52
  5. Step 5: Solve for x
    x = 263,324.52/639.86
  6. Step 6: Final answer
    x = 411.53

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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.