Finding the Fourth Proportional to 122.27, 168.72 and 78.67

Step by Step Solution

1. Step 1: Write the proportion equation
   122.27 : 168.72 = 78.67 : x
2. Step 2: Convert to fraction form
   122.27/168.72 = 78.67/x
3. Step 3: Cross multiply
   122.27x = 168.72 × 78.67
4. Step 4: Simplify right side
   122.27x = 13,272.39
5. Step 5: Solve for x
   x = 13,272.39/122.27
6. Step 6: Final answer
   x = 108.55