Finding the Fourth Proportional to 142,139.25, 196,152.11 and 81,721.71

Step by Step Solution

1. Step 1: Write the proportion equation
   142,139.25 : 196,152.11 = 81,721.71 : x
2. Step 2: Convert to fraction form
   142,139.25/196,152.11 = 81,721.71/x
3. Step 3: Cross multiply
   142,139.25x = 196,152.11 × 81,721.71
4. Step 4: Simplify right side
   142,139.25x = 16,029,884,868.55
5. Step 5: Solve for x
   x = 16,029,884,868.55/142,139.25
6. Step 6: Final answer
   x = 112,775.92