Finding the Fourth Proportional to 111.93, 154.27 and 78.74

Step by Step Solution

1. Step 1: Write the proportion equation
   111.93 : 154.27 = 78.74 : x
2. Step 2: Convert to fraction form
   111.93/154.27 = 78.74/x
3. Step 3: Cross multiply
   111.93x = 154.27 × 78.74
4. Step 4: Simplify right side
   111.93x = 12,147.02
5. Step 5: Solve for x
   x = 12,147.02/111.93
6. Step 6: Final answer
   x = 108.53