Finding the Fourth Proportional to 139,051.46, 191,879.20 and 78,613.72

Step by Step Solution

1. Step 1: Write the proportion equation
   139,051.46 : 191,879.20 = 78,613.72 : x
2. Step 2: Convert to fraction form
   139,051.46/191,879.20 = 78,613.72/x
3. Step 3: Cross multiply
   139,051.46x = 191,879.20 × 78,613.72
4. Step 4: Simplify right side
   139,051.46x = 15,084,337,702.62
5. Step 5: Solve for x
   x = 15,084,337,702.62/139,051.46
6. Step 6: Final answer
   x = 108,480.25