Finding the Fourth Proportional to 139,422.69, 192,387.70 and 78,980.39

Step by Step Solution

1. Step 1: Write the proportion equation
   139,422.69 : 192,387.70 = 78,980.39 : x
2. Step 2: Convert to fraction form
   139,422.69/192,387.70 = 78,980.39/x
3. Step 3: Cross multiply
   139,422.69x = 192,387.70 × 78,980.39
4. Step 4: Simplify right side
   139,422.69x = 15,194,854,991.18
5. Step 5: Solve for x
   x = 15,194,854,991.18/139,422.69
6. Step 6: Final answer
   x = 108,984.09