Finding the Fourth Proportional to 139.24, 192.02 and 111.60

Step by Step Solution

1. Step 1: Write the proportion equation
   139.24 : 192.02 = 111.60 : x
2. Step 2: Convert to fraction form
   139.24/192.02 = 111.60/x
3. Step 3: Cross multiply
   139.24x = 192.02 × 111.60
4. Step 4: Simplify right side
   139.24x = 21,429.71
5. Step 5: Solve for x
   x = 21,429.71/139.24
6. Step 6: Final answer
   x = 153.91