Finding the Fourth Proportional to 142,340.40, 196,437.42 and 78,684.12

Step by Step Solution

1. Step 1: Write the proportion equation
   142,340.40 : 196,437.42 = 78,684.12 : x
2. Step 2: Convert to fraction form
   142,340.40/196,437.42 = 78,684.12/x
3. Step 3: Cross multiply
   142,340.40x = 196,437.42 × 78,684.12
4. Step 4: Simplify right side
   142,340.40x = 15,456,505,527.77
5. Step 5: Solve for x
   x = 15,456,505,527.77/142,340.40
6. Step 6: Final answer
   x = 108,588.32