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Finding the Fourth Proportional to 87.11, 131.30 and 83.87

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Solution

The fourth proportional to 87.11, 131.30 and 83.87 is: 126.41

Step by Step Solution

  1. Step 1: Write the proportion equation
    87.11 : 131.30 = 83.87 : x
  2. Step 2: Convert to fraction form
    87.11/131.30 = 83.87/x
  3. Step 3: Cross multiply
    87.11x = 131.30 × 83.87
  4. Step 4: Simplify right side
    87.11x = 11,011.06
  5. Step 5: Solve for x
    x = 11,011.06/87.11
  6. Step 6: Final answer
    x = 126.41

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Why These Related Problems?

These problems maintain the same ratio (1.51) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.