Finding the Fourth Proportional to 139,142.16, 192,016.23 and 78,711.51

Step by Step Solution

1. Step 1: Write the proportion equation
   139,142.16 : 192,016.23 = 78,711.51 : x
2. Step 2: Convert to fraction form
   139,142.16/192,016.23 = 78,711.51/x
3. Step 3: Cross multiply
   139,142.16x = 192,016.23 × 78,711.51
4. Step 4: Simplify right side
   139,142.16x = 15,113,887,407.81
5. Step 5: Solve for x
   x = 15,113,887,407.81/139,142.16
6. Step 6: Final answer
   x = 108,621.91