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Finding the Fourth Proportional to 286.40, 428.82 and 199.55

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Solution

The fourth proportional to 286.40, 428.82 and 199.55 is: 298.78

Step by Step Solution

  1. Step 1: Write the proportion equation
    286.40 : 428.82 = 199.55 : x
  2. Step 2: Convert to fraction form
    286.40/428.82 = 199.55/x
  3. Step 3: Cross multiply
    286.40x = 428.82 × 199.55
  4. Step 4: Simplify right side
    286.40x = 85,568.89
  5. Step 5: Solve for x
    x = 85,568.89/286.40
  6. Step 6: Final answer
    x = 298.78

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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.