Finding the Fourth Proportional to 111.52, 153.78 and 86.96

Step by Step Solution

1. Step 1: Write the proportion equation
   111.52 : 153.78 = 86.96 : x
2. Step 2: Convert to fraction form
   111.52/153.78 = 86.96/x
3. Step 3: Cross multiply
   111.52x = 153.78 × 86.96
4. Step 4: Simplify right side
   111.52x = 13,372.71
5. Step 5: Solve for x
   x = 13,372.71/111.52
6. Step 6: Final answer
   x = 119.91