Finding the Fourth Proportional to 142,357.75, 196,436.67 and 78,686.89

Step by Step Solution

1. Step 1: Write the proportion equation
   142,357.75 : 196,436.67 = 78,686.89 : x
2. Step 2: Convert to fraction form
   142,357.75/196,436.67 = 78,686.89/x
3. Step 3: Cross multiply
   142,357.75x = 196,436.67 × 78,686.89
4. Step 4: Simplify right side
   142,357.75x = 15,456,990,644.26
5. Step 5: Solve for x
   x = 15,456,990,644.26/142,357.75
6. Step 6: Final answer
   x = 108,578.50