Finding the Fourth Proportional to 142.59, 196.78 and 113.17

Step by Step Solution

1. Step 1: Write the proportion equation
   142.59 : 196.78 = 113.17 : x
2. Step 2: Convert to fraction form
   142.59/196.78 = 113.17/x
3. Step 3: Cross multiply
   142.59x = 196.78 × 113.17
4. Step 4: Simplify right side
   142.59x = 22,269.59
5. Step 5: Solve for x
   x = 22,269.59/142.59
6. Step 6: Final answer
   x = 156.18