Just numbers
Level 1
Level 2
Level 3
Level 4
100

2x28

56

100

2(x+1)

2x+2

100

4(r-3)

4r-12
100

6(1-r)

6-r

100

x(1+y)

x+xy

200

5x18

90

200

3(x+2)

3x+6
200

7(w-4)

7w-28

200

8(4-t)

32-8t

200

t(3+g)

3t+tg

300

7x53

371

300

8(y+3)

8y+24

300

10(m-11)

10m-110

300

5(2-3x)

10-15x

300

4(1+x+y)

4+4x+4y

400

8x34

272

400

7(t+6)

7t+42

400

9(p-13)

9p-117

400

7(6-8s)

42-56s

400

11(4-e+f)

44-11e+11f

500

7x93

651

500

12(x+5)

12x+60

500

15(x-20)

15x-300

500

13(2-5f)

26-65f

500

7(3+2e-6f+3y)

21+14e-42f+21y