Finding the Fourth Proportional to 111.79, 154.29 and 85.53

Step by Step Solution

1. Step 1: Write the proportion equation
   111.79 : 154.29 = 85.53 : x
2. Step 2: Convert to fraction form
   111.79/154.29 = 85.53/x
3. Step 3: Cross multiply
   111.79x = 154.29 × 85.53
4. Step 4: Simplify right side
   111.79x = 13,196.42
5. Step 5: Solve for x
   x = 13,196.42/111.79
6. Step 6: Final answer
   x = 118.05