Finding the Fourth Proportional to 139,402.58, 192,369.27 and 78,971.99

Step by Step Solution

1. Step 1: Write the proportion equation
   139,402.58 : 192,369.27 = 78,971.99 : x
2. Step 2: Convert to fraction form
   139,402.58/192,369.27 = 78,971.99/x
3. Step 3: Cross multiply
   139,402.58x = 192,369.27 × 78,971.99
4. Step 4: Simplify right side
   139,402.58x = 15,191,783,104.90
5. Step 5: Solve for x
   x = 15,191,783,104.90/139,402.58
6. Step 6: Final answer
   x = 108,977.78