Finding the Fourth Proportional to 139,780.32, 192,904.94 and 105,263.25

Step by Step Solution

1. Step 1: Write the proportion equation
   139,780.32 : 192,904.94 = 105,263.25 : x
2. Step 2: Convert to fraction form
   139,780.32/192,904.94 = 105,263.25/x
3. Step 3: Cross multiply
   139,780.32x = 192,904.94 × 105,263.25
4. Step 4: Simplify right side
   139,780.32x = 20,305,800,399.14
5. Step 5: Solve for x
   x = 20,305,800,399.14/139,780.32
6. Step 6: Final answer
   x = 145,269.39