Finding the Fourth Proportional to 139.55, 192.53 and 80.51

Step by Step Solution

1. Step 1: Write the proportion equation
   139.55 : 192.53 = 80.51 : x
2. Step 2: Convert to fraction form
   139.55/192.53 = 80.51/x
3. Step 3: Cross multiply
   139.55x = 192.53 × 80.51
4. Step 4: Simplify right side
   139.55x = 15,499.83
5. Step 5: Solve for x
   x = 15,499.83/139.55
6. Step 6: Final answer
   x = 111.07