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Finding the Fourth Proportional to 511.71, 706.09 and 287.61

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Solution

The fourth proportional to 511.71, 706.09 and 287.61 is: 396.86

Step by Step Solution

  1. Step 1: Write the proportion equation
    511.71 : 706.09 = 287.61 : x
  2. Step 2: Convert to fraction form
    511.71/706.09 = 287.61/x
  3. Step 3: Cross multiply
    511.71x = 706.09 × 287.61
  4. Step 4: Simplify right side
    511.71x = 203,078.54
  5. Step 5: Solve for x
    x = 203,078.54/511.71
  6. Step 6: Final answer
    x = 396.86

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.