Finding the Fourth Proportional to 142,136.28, 196,086.42 and 81,693

Step by Step Solution

1. Step 1: Write the proportion equation
   142,136.28 : 196,086.42 = 81,693 : x
2. Step 2: Convert to fraction form
   142,136.28/196,086.42 = 81,693/x
3. Step 3: Cross multiply
   142,136.28x = 196,086.42 × 81,693
4. Step 4: Simplify right side
   142,136.28x = 16,018,887,909.06
5. Step 5: Solve for x
   x = 16,018,887,909.06/142,136.28
6. Step 6: Final answer
   x = 112,700.91