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Finding the Fourth Proportional to 87.09, 131.40 and 84.06

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Solution

The fourth proportional to 87.09, 131.40 and 84.06 is: 126.83

Step by Step Solution

  1. Step 1: Write the proportion equation
    87.09 : 131.40 = 84.06 : x
  2. Step 2: Convert to fraction form
    87.09/131.40 = 84.06/x
  3. Step 3: Cross multiply
    87.09x = 131.40 × 84.06
  4. Step 4: Simplify right side
    87.09x = 11,045.48
  5. Step 5: Solve for x
    x = 11,045.48/87.09
  6. Step 6: Final answer
    x = 126.83

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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.