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Finding the Fourth Proportional to 87.69, 121.57 and 82.83

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Solution

The fourth proportional to 87.69, 121.57 and 82.83 is: 114.83

Step by Step Solution

  1. Step 1: Write the proportion equation
    87.69 : 121.57 = 82.83 : x
  2. Step 2: Convert to fraction form
    87.69/121.57 = 82.83/x
  3. Step 3: Cross multiply
    87.69x = 121.57 × 82.83
  4. Step 4: Simplify right side
    87.69x = 10,068.62
  5. Step 5: Solve for x
    x = 10,068.62/87.69
  6. Step 6: Final answer
    x = 114.83

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Why These Related Problems?

These problems maintain the same ratio (1.39) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.