Finding the Fourth Proportional to 139.24, 208.60 and 111.89

Step by Step Solution

1. Step 1: Write the proportion equation
   139.24 : 208.60 = 111.89 : x
2. Step 2: Convert to fraction form
   139.24/208.60 = 111.89/x
3. Step 3: Cross multiply
   139.24x = 208.60 × 111.89
4. Step 4: Simplify right side
   139.24x = 23,340.25
5. Step 5: Solve for x
   x = 23,340.25/139.24
6. Step 6: Final answer
   x = 167.63