Finding the Fourth Proportional to 108,688.10, 149,920.54 and 78,517.76

Step by Step Solution

1. Step 1: Write the proportion equation
   108,688.10 : 149,920.54 = 78,517.76 : x
2. Step 2: Convert to fraction form
   108,688.10/149,920.54 = 78,517.76/x
3. Step 3: Cross multiply
   108,688.10x = 149,920.54 × 78,517.76
4. Step 4: Simplify right side
   108,688.10x = 11,771,424,032.89
5. Step 5: Solve for x
   x = 11,771,424,032.89/108,688.10
6. Step 6: Final answer
   x = 108,304.63