Finding the Fourth Proportional to 139,939.28, 209,759.25 and 79,838.25

Step by Step Solution

1. Step 1: Write the proportion equation
   139,939.28 : 209,759.25 = 79,838.25 : x
2. Step 2: Convert to fraction form
   139,939.28/209,759.25 = 79,838.25/x
3. Step 3: Cross multiply
   139,939.28x = 209,759.25 × 79,838.25
4. Step 4: Simplify right side
   139,939.28x = 16,746,811,441.31
5. Step 5: Solve for x
   x = 16,746,811,441.31/139,939.28
6. Step 6: Final answer
   x = 119,671.99