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Finding the Fourth Proportional to 80.98, 121.61 and 72.32

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Solution

The fourth proportional to 80.98, 121.61 and 72.32 is: 108.61

Step by Step Solution

  1. Step 1: Write the proportion equation
    80.98 : 121.61 = 72.32 : x
  2. Step 2: Convert to fraction form
    80.98/121.61 = 72.32/x
  3. Step 3: Cross multiply
    80.98x = 121.61 × 72.32
  4. Step 4: Simplify right side
    80.98x = 8,794.84
  5. Step 5: Solve for x
    x = 8,794.84/80.98
  6. Step 6: Final answer
    x = 108.61

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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.