Finding the Fourth Proportional to 111.69, 153.98 and 86.83

Step by Step Solution

1. Step 1: Write the proportion equation
   111.69 : 153.98 = 86.83 : x
2. Step 2: Convert to fraction form
   111.69/153.98 = 86.83/x
3. Step 3: Cross multiply
   111.69x = 153.98 × 86.83
4. Step 4: Simplify right side
   111.69x = 13,370.08
5. Step 5: Solve for x
   x = 13,370.08/111.69
6. Step 6: Final answer
   x = 119.71