Finding the Fourth Proportional to 139,856.15, 192,986.99 and 78,592.61

Step by Step Solution

1. Step 1: Write the proportion equation
   139,856.15 : 192,986.99 = 78,592.61 : x
2. Step 2: Convert to fraction form
   139,856.15/192,986.99 = 78,592.61/x
3. Step 3: Cross multiply
   139,856.15x = 192,986.99 × 78,592.61
4. Step 4: Simplify right side
   139,856.15x = 15,167,351,624.37
5. Step 5: Solve for x
   x = 15,167,351,624.37/139,856.15
6. Step 6: Final answer
   x = 108,449.66