Answer :

2+2

4

4+4

8

8+6

14

14-4

10

10+3

13

13-2

11

11+7

18

18+6

24

24+6

30

30+6

36

36+6

42 is the answer

just group like numbers
in increasing numbers
2+2+4+6-4+3-2+7+24
2+2-2+3+4-4+6+6+6+6+6+7
2+(2-2)+3+(4-4)+(6+6+6+6+6)+(7)
2+(0)+(0)+3+(30)+7
2+30+3+7
2+30+10
40+2
42