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Finding the Fourth Proportional to 869.82, 1,198.62 and 620.70

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Solution

The fourth proportional to 869.82, 1,198.62 and 620.70 is: 855.33

Step by Step Solution

  1. Step 1: Write the proportion equation
    869.82 : 1,198.62 = 620.70 : x
  2. Step 2: Convert to fraction form
    869.82/1,198.62 = 620.70/x
  3. Step 3: Cross multiply
    869.82x = 1,198.62 × 620.70
  4. Step 4: Simplify right side
    869.82x = 743,983.43
  5. Step 5: Solve for x
    x = 743,983.43/869.82
  6. Step 6: Final answer
    x = 855.33

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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.