Finding the Fourth Proportional to 142,146.90, 196,165.78 and 78,488.72

Step by Step Solution

1. Step 1: Write the proportion equation
   142,146.90 : 196,165.78 = 78,488.72 : x
2. Step 2: Convert to fraction form
   142,146.90/196,165.78 = 78,488.72/x
3. Step 3: Cross multiply
   142,146.90x = 196,165.78 × 78,488.72
4. Step 4: Simplify right side
   142,146.90x = 15,396,800,980.00
5. Step 5: Solve for x
   x = 15,396,800,980.00/142,146.90
6. Step 6: Final answer
   x = 108,316.12