Finding the Fourth Proportional to 139.32, 208.04 and 111.78

Step by Step Solution

1. Step 1: Write the proportion equation
   139.32 : 208.04 = 111.78 : x
2. Step 2: Convert to fraction form
   139.32/208.04 = 111.78/x
3. Step 3: Cross multiply
   139.32x = 208.04 × 111.78
4. Step 4: Simplify right side
   139.32x = 23,254.15
5. Step 5: Solve for x
   x = 23,254.15/139.32
6. Step 6: Final answer
   x = 166.91