Finding the Fourth Proportional to 105.94, 146.12 and 78.38

Step by Step Solution

1. Step 1: Write the proportion equation
   105.94 : 146.12 = 78.38 : x
2. Step 2: Convert to fraction form
   105.94/146.12 = 78.38/x
3. Step 3: Cross multiply
   105.94x = 146.12 × 78.38
4. Step 4: Simplify right side
   105.94x = 11,452.89
5. Step 5: Solve for x
   x = 11,452.89/105.94
6. Step 6: Final answer
   x = 108.11