Finding the Fourth Proportional to 142,654.77, 196,861.18 and 78,991.20

Step by Step Solution

1. Step 1: Write the proportion equation
   142,654.77 : 196,861.18 = 78,991.20 : x
2. Step 2: Convert to fraction form
   142,654.77/196,861.18 = 78,991.20/x
3. Step 3: Cross multiply
   142,654.77x = 196,861.18 × 78,991.20
4. Step 4: Simplify right side
   142,654.77x = 15,550,300,644.14
5. Step 5: Solve for x
   x = 15,550,300,644.14/142,654.77
6. Step 6: Final answer
   x = 109,006.52