Finding the Fourth Proportional to 139.39, 192.27 and 90.25

Step by Step Solution

1. Step 1: Write the proportion equation
   139.39 : 192.27 = 90.25 : x
2. Step 2: Convert to fraction form
   139.39/192.27 = 90.25/x
3. Step 3: Cross multiply
   139.39x = 192.27 × 90.25
4. Step 4: Simplify right side
   139.39x = 17,352.37
5. Step 5: Solve for x
   x = 17,352.37/139.39
6. Step 6: Final answer
   x = 124.49