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Finding the Fourth Proportional to 286.20, 429.30 and 199.80

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Solution

The fourth proportional to 286.20, 429.30 and 199.80 is: 299.70

Step by Step Solution

  1. Step 1: Write the proportion equation
    286.20 : 429.30 = 199.80 : x
  2. Step 2: Convert to fraction form
    286.20/429.30 = 199.80/x
  3. Step 3: Cross multiply
    286.20x = 429.30 × 199.80
  4. Step 4: Simplify right side
    286.20x = 85,774.14
  5. Step 5: Solve for x
    x = 85,774.14/286.20
  6. Step 6: Final answer
    x = 299.70

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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.