Finding the Fourth Proportional to 139,305.50, 192,241.59 and 79,689.50

Step by Step Solution

1. Step 1: Write the proportion equation
   139,305.50 : 192,241.59 = 79,689.50 : x
2. Step 2: Convert to fraction form
   139,305.50/192,241.59 = 79,689.50/x
3. Step 3: Cross multiply
   139,305.50x = 192,241.59 × 79,689.50
4. Step 4: Simplify right side
   139,305.50x = 15,319,636,186.31
5. Step 5: Solve for x
   x = 15,319,636,186.31/139,305.50
6. Step 6: Final answer
   x = 109,971.51