Finding the Fourth Proportional to 111.56, 153.82 and 90.79

Step by Step Solution

1. Step 1: Write the proportion equation
   111.56 : 153.82 = 90.79 : x
2. Step 2: Convert to fraction form
   111.56/153.82 = 90.79/x
3. Step 3: Cross multiply
   111.56x = 153.82 × 90.79
4. Step 4: Simplify right side
   111.56x = 13,965.70
5. Step 5: Solve for x
   x = 13,965.70/111.56
6. Step 6: Final answer
   x = 125.19