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Finding the Fourth Proportional to 86.19, 129.03 and 80.34

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Solution

The fourth proportional to 86.19, 129.03 and 80.34 is: 120.27

Step by Step Solution

  1. Step 1: Write the proportion equation
    86.19 : 129.03 = 80.34 : x
  2. Step 2: Convert to fraction form
    86.19/129.03 = 80.34/x
  3. Step 3: Cross multiply
    86.19x = 129.03 × 80.34
  4. Step 4: Simplify right side
    86.19x = 10,366.27
  5. Step 5: Solve for x
    x = 10,366.27/86.19
  6. Step 6: Final answer
    x = 120.27

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.