Finding the Fourth Proportional to 105.73, 158.29 and 78.19

Step by Step Solution

1. Step 1: Write the proportion equation
   105.73 : 158.29 = 78.19 : x
2. Step 2: Convert to fraction form
   105.73/158.29 = 78.19/x
3. Step 3: Cross multiply
   105.73x = 158.29 × 78.19
4. Step 4: Simplify right side
   105.73x = 12,376.10
5. Step 5: Solve for x
   x = 12,376.10/105.73
6. Step 6: Final answer
   x = 117.06