Finding the Fourth Proportional to 111.22, 153.50 and 83.68

Step by Step Solution

1. Step 1: Write the proportion equation
   111.22 : 153.50 = 83.68 : x
2. Step 2: Convert to fraction form
   111.22/153.50 = 83.68/x
3. Step 3: Cross multiply
   111.22x = 153.50 × 83.68
4. Step 4: Simplify right side
   111.22x = 12,844.88
5. Step 5: Solve for x
   x = 12,844.88/111.22
6. Step 6: Final answer
   x = 115.49