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Finding the Fourth Proportional to 87.28, 121.01 and 83.17

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Solution

The fourth proportional to 87.28, 121.01 and 83.17 is: 115.31

Step by Step Solution

  1. Step 1: Write the proportion equation
    87.28 : 121.01 = 83.17 : x
  2. Step 2: Convert to fraction form
    87.28/121.01 = 83.17/x
  3. Step 3: Cross multiply
    87.28x = 121.01 × 83.17
  4. Step 4: Simplify right side
    87.28x = 10,063.80
  5. Step 5: Solve for x
    x = 10,063.80/87.28
  6. Step 6: Final answer
    x = 115.31

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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.