Finding the Fourth Proportional to 105.96, 146.22 and 78.42

Step by Step Solution

1. Step 1: Write the proportion equation
   105.96 : 146.22 = 78.42 : x
2. Step 2: Convert to fraction form
   105.96/146.22 = 78.42/x
3. Step 3: Cross multiply
   105.96x = 146.22 × 78.42
4. Step 4: Simplify right side
   105.96x = 11,466.57
5. Step 5: Solve for x
   x = 11,466.57/105.96
6. Step 6: Final answer
   x = 108.22