Finding the Fourth Proportional to 142,170.72, 196,191.90 and 91,131

Step by Step Solution

1. Step 1: Write the proportion equation
   142,170.72 : 196,191.90 = 91,131 : x
2. Step 2: Convert to fraction form
   142,170.72/196,191.90 = 91,131/x
3. Step 3: Cross multiply
   142,170.72x = 196,191.90 × 91,131
4. Step 4: Simplify right side
   142,170.72x = 17,879,164,038.90
5. Step 5: Solve for x
   x = 17,879,164,038.90/142,170.72
6. Step 6: Final answer
   x = 125,758.41