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Finding the Fourth Proportional to 639.13, 958.31 and 326.59

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Solution

The fourth proportional to 639.13, 958.31 and 326.59 is: 489.69

Step by Step Solution

  1. Step 1: Write the proportion equation
    639.13 : 958.31 = 326.59 : x
  2. Step 2: Convert to fraction form
    639.13/958.31 = 326.59/x
  3. Step 3: Cross multiply
    639.13x = 958.31 × 326.59
  4. Step 4: Simplify right side
    639.13x = 312,974.46
  5. Step 5: Solve for x
    x = 312,974.46/639.13
  6. Step 6: Final answer
    x = 489.69

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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.