Finding the Fourth Proportional to 139.69, 208.58 and 134.56

Step by Step Solution

1. Step 1: Write the proportion equation
   139.69 : 208.58 = 134.56 : x
2. Step 2: Convert to fraction form
   139.69/208.58 = 134.56/x
3. Step 3: Cross multiply
   139.69x = 208.58 × 134.56
4. Step 4: Simplify right side
   139.69x = 28,066.52
5. Step 5: Solve for x
   x = 28,066.52/139.69
6. Step 6: Final answer
   x = 200.92