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Finding the Fourth Proportional to 636.80, 878.28 and 426.91

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Solution

The fourth proportional to 636.80, 878.28 and 426.91 is: 588.79

Step by Step Solution

  1. Step 1: Write the proportion equation
    636.80 : 878.28 = 426.91 : x
  2. Step 2: Convert to fraction form
    636.80/878.28 = 426.91/x
  3. Step 3: Cross multiply
    636.80x = 878.28 × 426.91
  4. Step 4: Simplify right side
    636.80x = 374,942.12
  5. Step 5: Solve for x
    x = 374,942.12/636.80
  6. Step 6: Final answer
    x = 588.79

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.