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Finding the Fourth Proportional to 87.06, 120.26 and 80.58

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Solution

The fourth proportional to 87.06, 120.26 and 80.58 is: 111.31

Step by Step Solution

  1. Step 1: Write the proportion equation
    87.06 : 120.26 = 80.58 : x
  2. Step 2: Convert to fraction form
    87.06/120.26 = 80.58/x
  3. Step 3: Cross multiply
    87.06x = 120.26 × 80.58
  4. Step 4: Simplify right side
    87.06x = 9,690.55
  5. Step 5: Solve for x
    x = 9,690.55/87.06
  6. Step 6: Final answer
    x = 111.31

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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.