Finding the Fourth Proportional to 111.48, 153.74 and 90.72

Step by Step Solution

1. Step 1: Write the proportion equation
   111.48 : 153.74 = 90.72 : x
2. Step 2: Convert to fraction form
   111.48/153.74 = 90.72/x
3. Step 3: Cross multiply
   111.48x = 153.74 × 90.72
4. Step 4: Simplify right side
   111.48x = 13,947.29
5. Step 5: Solve for x
   x = 13,947.29/111.48
6. Step 6: Final answer
   x = 125.11