Finding the Fourth Proportional to 111.30, 153.42 and 90.48

Step by Step Solution

1. Step 1: Write the proportion equation
   111.30 : 153.42 = 90.48 : x
2. Step 2: Convert to fraction form
   111.30/153.42 = 90.48/x
3. Step 3: Cross multiply
   111.30x = 153.42 × 90.48
4. Step 4: Simplify right side
   111.30x = 13,881.44
5. Step 5: Solve for x
   x = 13,881.44/111.30
6. Step 6: Final answer
   x = 124.72