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Finding the Fourth Proportional to 299.78, 411.23 and 287.18

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Solution

The fourth proportional to 299.78, 411.23 and 287.18 is: 393.94

Step by Step Solution

  1. Step 1: Write the proportion equation
    299.78 : 411.23 = 287.18 : x
  2. Step 2: Convert to fraction form
    299.78/411.23 = 287.18/x
  3. Step 3: Cross multiply
    299.78x = 411.23 × 287.18
  4. Step 4: Simplify right side
    299.78x = 118,093.54
  5. Step 5: Solve for x
    x = 118,093.54/299.78
  6. Step 6: Final answer
    x = 393.94

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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.