Finding the Fourth Proportional to 139.42, 208.27 and 136.72

Step by Step Solution

1. Step 1: Write the proportion equation
   139.42 : 208.27 = 136.72 : x
2. Step 2: Convert to fraction form
   139.42/208.27 = 136.72/x
3. Step 3: Cross multiply
   139.42x = 208.27 × 136.72
4. Step 4: Simplify right side
   139.42x = 28,474.67
5. Step 5: Solve for x
   x = 28,474.67/139.42
6. Step 6: Final answer
   x = 204.24