Finding the Fourth Proportional to 139.29, 208.94 and 82.25

Step by Step Solution

1. Step 1: Write the proportion equation
   139.29 : 208.94 = 82.25 : x
2. Step 2: Convert to fraction form
   139.29/208.94 = 82.25/x
3. Step 3: Cross multiply
   139.29x = 208.94 × 82.25
4. Step 4: Simplify right side
   139.29x = 17,185.32
5. Step 5: Solve for x
   x = 17,185.32/139.29
6. Step 6: Final answer
   x = 123.38