1 digit x 2 digit
34 x 3
102
223 x 4
892
2145 x 4
8580
Estimate:
72 x 18
70 x 20 = 1400
44 x 20
40 x 20 = 800
4 x 20 = 80
880
45 x 4
180
345 x 5
1725
3614 x 3
10842
Estimate:
36 x 47
40 x 50 = 2000
56 x 70
50 x 70 = 3500
6 x 70 = 420
3920
66 x 8
528
409 x 6
2454
5375 x 7
37625
Estimate:
84 x 32
80 x 30 = 2400
73 x 40
70 x 40 = 2800
3 x 40 = 120
2920
79 x 6
474
742 x 7
5194
6290 x 8
50320
Estimate:
785 x 72
800 x 70 = 56000
89 x 30
80 x 30 = 2400
9 x 30 = 270
2670
98 x 9
882
965 x 8
7720
5314 x 9
47826
Estimate:
957 x 34
1000 X 30 = 30000
78 x 90
70 x 90 = 6300
8 x 90 = 720
7020