Finding the Fourth Proportional to 111.48, 153.64 and 83.76

Step by Step Solution

1. Step 1: Write the proportion equation
   111.48 : 153.64 = 83.76 : x
2. Step 2: Convert to fraction form
   111.48/153.64 = 83.76/x
3. Step 3: Cross multiply
   111.48x = 153.64 × 83.76
4. Step 4: Simplify right side
   111.48x = 12,868.89
5. Step 5: Solve for x
   x = 12,868.89/111.48
6. Step 6: Final answer
   x = 115.44