Finding the Fourth Proportional to 111.69, 154.11 and 65.05

Step by Step Solution

1. Step 1: Write the proportion equation
   111.69 : 154.11 = 65.05 : x
2. Step 2: Convert to fraction form
   111.69/154.11 = 65.05/x
3. Step 3: Cross multiply
   111.69x = 154.11 × 65.05
4. Step 4: Simplify right side
   111.69x = 10,024.59
5. Step 5: Solve for x
   x = 10,024.59/111.69
6. Step 6: Final answer
   x = 89.76