Finding the Fourth Proportional to 139.37, 192.24 and 90.23

Step by Step Solution

1. Step 1: Write the proportion equation
   139.37 : 192.24 = 90.23 : x
2. Step 2: Convert to fraction form
   139.37/192.24 = 90.23/x
3. Step 3: Cross multiply
   139.37x = 192.24 × 90.23
4. Step 4: Simplify right side
   139.37x = 17,345.94
5. Step 5: Solve for x
   x = 17,345.94/139.37
6. Step 6: Final answer
   x = 124.46