Multiply by 3 and 4
7 x 3
21
7 x 3
21
4 x 80
320
6 x (3 x 3)
54
6 x 4
24
3 x 3
9
7 x 7
49
6 x 70
420
(2 x 4) x 6
48
6 x 6
36
3 x 9
27
56
90 x 5
450
(3 x 2) x 7
42
6 x 7
42
4 x 7
28
8 x 8
64
50 x 7
350
4 x 2 x 3
24
6 x 9
54
4 x 9
36
8 x 9
72
20 x 9
180
8 x 2 x 2
32
6 x 8
48