Finding the Fourth Proportional to 142,446.20, 196,579.71 and 78,788.09

Step by Step Solution

1. Step 1: Write the proportion equation
   142,446.20 : 196,579.71 = 78,788.09 : x
2. Step 2: Convert to fraction form
   142,446.20/196,579.71 = 78,788.09/x
3. Step 3: Cross multiply
   142,446.20x = 196,579.71 × 78,788.09
4. Step 4: Simplify right side
   142,446.20x = 15,488,140,375.10
5. Step 5: Solve for x
   x = 15,488,140,375.10/142,446.20
6. Step 6: Final answer
   x = 108,729.76