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Finding the Fourth Proportional to 799.21, 1,198.81 and 279.19

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Solution

The fourth proportional to 799.21, 1,198.81 and 279.19 is: 418.78

Step by Step Solution

  1. Step 1: Write the proportion equation
    799.21 : 1,198.81 = 279.19 : x
  2. Step 2: Convert to fraction form
    799.21/1,198.81 = 279.19/x
  3. Step 3: Cross multiply
    799.21x = 1,198.81 × 279.19
  4. Step 4: Simplify right side
    799.21x = 334,689.77
  5. Step 5: Solve for x
    x = 334,689.77/799.21
  6. Step 6: Final answer
    x = 418.78

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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.