Finding the Fourth Proportional to 111.26, 153.54 and 83.57

Step by Step Solution

1. Step 1: Write the proportion equation
   111.26 : 153.54 = 83.57 : x
2. Step 2: Convert to fraction form
   111.26/153.54 = 83.57/x
3. Step 3: Cross multiply
   111.26x = 153.54 × 83.57
4. Step 4: Simplify right side
   111.26x = 12,831.34
5. Step 5: Solve for x
   x = 12,831.34/111.26
6. Step 6: Final answer
   x = 115.33