Finding the Fourth Proportional to 139,003.75, 191,828.12 and 78,570.79

Step by Step Solution

1. Step 1: Write the proportion equation
   139,003.75 : 191,828.12 = 78,570.79 : x
2. Step 2: Convert to fraction form
   139,003.75/191,828.12 = 78,570.79/x
3. Step 3: Cross multiply
   139,003.75x = 191,828.12 × 78,570.79
4. Step 4: Simplify right side
   139,003.75x = 15,072,086,932.61
5. Step 5: Solve for x
   x = 15,072,086,932.61/139,003.75
6. Step 6: Final answer
   x = 108,429.35