Finding the Fourth Proportional to 139,077.59, 191,931.71 and 78,658.07

Step by Step Solution

1. Step 1: Write the proportion equation
   139,077.59 : 191,931.71 = 78,658.07 : x
2. Step 2: Convert to fraction form
   139,077.59/191,931.71 = 78,658.07/x
3. Step 3: Cross multiply
   139,077.59x = 191,931.71 × 78,658.07
4. Step 4: Simplify right side
   139,077.59x = 15,096,976,527.45
5. Step 5: Solve for x
   x = 15,096,976,527.45/139,077.59
6. Step 6: Final answer
   x = 108,550.75