Finding the Fourth Proportional to 139.59, 209.25 and 103.68

Step by Step Solution

1. Step 1: Write the proportion equation
   139.59 : 209.25 = 103.68 : x
2. Step 2: Convert to fraction form
   139.59/209.25 = 103.68/x
3. Step 3: Cross multiply
   139.59x = 209.25 × 103.68
4. Step 4: Simplify right side
   139.59x = 21,694.52
5. Step 5: Solve for x
   x = 21,694.52/139.59
6. Step 6: Final answer
   x = 155.42