Finding the Fourth Proportional to 142,654.31, 196,860.53 and 78,990.74

Step by Step Solution

1. Step 1: Write the proportion equation
   142,654.31 : 196,860.53 = 78,990.74 : x
2. Step 2: Convert to fraction form
   142,654.31/196,860.53 = 78,990.74/x
3. Step 3: Cross multiply
   142,654.31x = 196,860.53 × 78,990.74
4. Step 4: Simplify right side
   142,654.31x = 15,550,158,523.78
5. Step 5: Solve for x
   x = 15,550,158,523.78/142,654.31
6. Step 6: Final answer
   x = 109,005.88