Finding the Fourth Proportional to 142.79, 196.89 and 105.84

Step by Step Solution

1. Step 1: Write the proportion equation
   142.79 : 196.89 = 105.84 : x
2. Step 2: Convert to fraction form
   142.79/196.89 = 105.84/x
3. Step 3: Cross multiply
   142.79x = 196.89 × 105.84
4. Step 4: Simplify right side
   142.79x = 20,838.44
5. Step 5: Solve for x
   x = 20,838.44/142.79
6. Step 6: Final answer
   x = 145.94