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Finding the Fourth Proportional to 299.85, 411.21 and 287.38

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Solution

The fourth proportional to 299.85, 411.21 and 287.38 is: 394.10

Step by Step Solution

  1. Step 1: Write the proportion equation
    299.85 : 411.21 = 287.38 : x
  2. Step 2: Convert to fraction form
    299.85/411.21 = 287.38/x
  3. Step 3: Cross multiply
    299.85x = 411.21 × 287.38
  4. Step 4: Simplify right side
    299.85x = 118,171.47
  5. Step 5: Solve for x
    x = 118,171.47/299.85
  6. Step 6: Final answer
    x = 394.10

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Why These Related Problems?

These problems maintain the same ratio (1.37) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.