Finding the Fourth Proportional to 142,090.98, 196,085.74 and 78,428.78

Step by Step Solution

1. Step 1: Write the proportion equation
   142,090.98 : 196,085.74 = 78,428.78 : x
2. Step 2: Convert to fraction form
   142,090.98/196,085.74 = 78,428.78/x
3. Step 3: Cross multiply
   142,090.98x = 196,085.74 × 78,428.78
4. Step 4: Simplify right side
   142,090.98x = 15,378,765,400.38
5. Step 5: Solve for x
   x = 15,378,765,400.38/142,090.98
6. Step 6: Final answer
   x = 108,231.82