Finding the Fourth Proportional to 172,300.05, 258,450.07 and 78,740.19

Step by Step Solution

1. Step 1: Write the proportion equation
   172,300.05 : 258,450.07 = 78,740.19 : x
2. Step 2: Convert to fraction form
   172,300.05/258,450.07 = 78,740.19/x
3. Step 3: Cross multiply
   172,300.05x = 258,450.07 × 78,740.19
4. Step 4: Simplify right side
   172,300.05x = 20,350,407,617.31
5. Step 5: Solve for x
   x = 20,350,407,617.31/172,300.05
6. Step 6: Final answer
   x = 118,110.28