Finding the Fourth Proportional to 142,128.57, 196,136.22 and 78,465

Step by Step Solution

1. Step 1: Write the proportion equation
   142,128.57 : 196,136.22 = 78,465 : x
2. Step 2: Convert to fraction form
   142,128.57/196,136.22 = 78,465/x
3. Step 3: Cross multiply
   142,128.57x = 196,136.22 × 78,465
4. Step 4: Simplify right side
   142,128.57x = 15,389,828,502.30
5. Step 5: Solve for x
   x = 15,389,828,502.30/142,128.57
6. Step 6: Final answer
   x = 108,281.03