Let's solve it step by step:
(we start with the innermost bracket: (25/5). This is equal to 5. :
25+{2[3+8-7(25/5)+11]} =
25+{2[3+8-7(5)+11]} =
now, we can multiply 7 and 5, which is 35
25+{2[3+8-35+11]} =
Now we can add all the numbers in the square bracket, 3,8 (that's 11), then -35 (which is -24) then 11 - all together it's -13
3+8-35+11=22-35=-13
25+{2[-13]} =
Multiplying 2 and -13
25+{-26} =25-26, which is -1
the final answer is -1