Finding the Fourth Proportional to 105.92, 146.06 and 74.78

Step by Step Solution

1. Step 1: Write the proportion equation
   105.92 : 146.06 = 74.78 : x
2. Step 2: Convert to fraction form
   105.92/146.06 = 74.78/x
3. Step 3: Cross multiply
   105.92x = 146.06 × 74.78
4. Step 4: Simplify right side
   105.92x = 10,922.37
5. Step 5: Solve for x
   x = 10,922.37/105.92
6. Step 6: Final answer
   x = 103.12