Finding the Fourth Proportional to 111.69, 154.15 and 65.07

Step by Step Solution

1. Step 1: Write the proportion equation
   111.69 : 154.15 = 65.07 : x
2. Step 2: Convert to fraction form
   111.69/154.15 = 65.07/x
3. Step 3: Cross multiply
   111.69x = 154.15 × 65.07
4. Step 4: Simplify right side
   111.69x = 10,030.38
5. Step 5: Solve for x
   x = 10,030.38/111.69
6. Step 6: Final answer
   x = 89.81