1.直接写出得数。
9×12=
2.5×12=
5×17=
60÷12=
48÷12=
15×12=
5.7×12=
3.4×12=
3.7×12=
84÷12=
240÷12=
4.5×12=

9×12=108
2.5×12=30
5×17=85
60÷12=5
48÷12=4
15×12=180
5.7×12=68.4
3.4×12=40.8
3.7×12=44.4
84÷12=7
240÷12=20
4.5×12=54

2.脱式计算。
(5+4+2)×4
(2.7+3+4.3)×4
(8+6+4)×4
(5.5+5+4.5)×4
(7+5+3)×4
(12.4+7.6+5)×4
240÷4-50
56÷4-5
52÷4-8
48÷4-7
(3.2+1.8+6)×4
(17+12+23)×4

(5+4+2)×4
=11×4
=44
(2.7+3+4.3)×4
=(2.7+4.3+3)×4
=(7+3)×4
=10×4
=40
(8+6+4)×4
=18×4
=72
(5.5+5+4.5)×4
=(5.5+4.5+5)×4
=(10+5)×4
=15×4
=60
(7+5+3)×4
=15×4
=60
(12.4+7.6+5)×4
=(20+5)×4
=25×4
=100
240÷4-50
=60-50
=10
56÷4-5
=14-5
=9
52÷4-8
=13-8
=5
48÷4-7
=12-7
=5
(3.2+1.8+6)×4
=(5+6)×4
=11×4
=44
(17+12+23)×4
=(17+23+12)×4
=(40+12)×4
=52×4
=208