Finding the Fourth Proportional to 111.55, 153.94 and 83.87

Step by Step Solution

1. Step 1: Write the proportion equation
   111.55 : 153.94 = 83.87 : x
2. Step 2: Convert to fraction form
   111.55/153.94 = 83.87/x
3. Step 3: Cross multiply
   111.55x = 153.94 × 83.87
4. Step 4: Simplify right side
   111.55x = 12,910.26
5. Step 5: Solve for x
   x = 12,910.26/111.55
6. Step 6: Final answer
   x = 115.74