Finding the Fourth Proportional to 105,690.40, 145,852.71 and 57,942.72

Step by Step Solution

1. Step 1: Write the proportion equation
   105,690.40 : 145,852.71 = 57,942.72 : x
2. Step 2: Convert to fraction form
   105,690.40/145,852.71 = 57,942.72/x
3. Step 3: Cross multiply
   105,690.40x = 145,852.71 × 57,942.72
4. Step 4: Simplify right side
   105,690.40x = 8,451,102,736.77
5. Step 5: Solve for x
   x = 8,451,102,736.77/105,690.40
6. Step 6: Final answer
   x = 79,960.93