Finding the Fourth Proportional to 111.94, 168.09 and 90.34

Step by Step Solution

1. Step 1: Write the proportion equation
   111.94 : 168.09 = 90.34 : x
2. Step 2: Convert to fraction form
   111.94/168.09 = 90.34/x
3. Step 3: Cross multiply
   111.94x = 168.09 × 90.34
4. Step 4: Simplify right side
   111.94x = 15,185.25
5. Step 5: Solve for x
   x = 15,185.25/111.94
6. Step 6: Final answer
   x = 135.66