a) X x 5 = 40
X = 40 : 5
X = 8
b) X : 4 = 5
X = 4 x 5
X = 20
c) X – 4 = 6
X = 6 + 4
X = 10
a)X x 5 = 40
X= 40 : 5
X=8
b)X : 4 =5
X = 5 x 4
X = 20
c)X - 4 = 6
X=6 + 4
X=10
8,20 và 10 nha
a, Y x 5 – 15 = 40
b, 75 – y x 5 = 30
Tìm x biết:
a, (x + 72) × 4 = 320
b, (x - 56) × 7 = 749
c, (x + 3) × 4 = 36
d, (x - 5) × 6 = 72
Điền > < =
a) 3 x 5 ..... 3 x 6
3 x 5 ..... 3x 4
b) 3 x 5 ..... 5 x 3
4 x 6 ..... 6 x 4
c) 20 : 4 ..... 20 : 5
20 : 4 ..... 20 : 2
Tính nhẩm
a) 6 x 2 = ..... 6 x 3 = ..... 6 x 8 = ..... 6 x 1 = .....
6 x 4 = ..... 6 x 5 = ..... 6 x 9 = ..... 1 x 6 = .....
6 x 6 = ..... 6 x 7 = ..... 6 x 10 = ..... 0 x 6 = .....
b) 6 x 5 = ..... 6 x 4 = ..... 3 x 6 = ..... 2 x 6 = .....
5 x 6 = ..... 4 x 6 = ..... 6 x 3 = ..... 6 x 2 = .....
Tìm x
a) 12 : x = 3 b) 21 : x = 7 c) 30 : x = 3
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d) X : 7 = 4 e) 20 : x = 5 f) X x 6 = 42
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Tính nhẩm:
a) 2 x 2 = ...... 3 x 3 = ......
2 x 4 = ...... 3 x 5 = ......
2 x 6 = ...... 3 x 7 = ......
2 x 8 = ...... 3 x 9 = ......
4 x 4 = ...... 5 x 5 = ......
4 x 2 = ...... 5 x 7 = ......
4 x 6 = ...... 5 x 9 = ......
4 x 8 = ...... 5 x 3 = ......
b) 200 x 4 = ...... 300 x 2 = ......
200 x 2 = ...... 300 x 3 = ......
400 x 2 = ...... 500 x 1 = ......
100 x 4 = ...... 100 x 3 = ......
Tính nhẩm
3 x 4 = 2 x 6 = 4 x 3 = 5 x 6 =
3 x 7 = 2 x 8 = 4 x 7 = 5 x 4 =
3 x 5 = 2 x 4 = 4 x 9 = 5 x 7 =
3 x 8 = 2 x 9 = 4 x 4 = 5 x 9 =
a .(18 – 9 x 2) x (2 + 4 + 6 + 8 + 10)
b.(7 x 8 – 56 ) : (2 + 4 + 6 + 8 + 112)
c. (2 + 125 + 6 + 145 + 112) x (42 – 6 x 7)
d.(12 x 6 – 12 x 4 – 12 x 2) x ( 347 + 125)
e(a x 7 + a x 8 – a x 15) : (1 + 2 + 3 + ........ + 10)
f.58 – 58 x (6 + 54 – 60)
g.32 + 63 x a x ( a x 1 – a : 1) + 32 x 8 + 32
h.(1 + 2 + 3 + 4 + .... + 9) x (21 x 5 – 21 – 4 x21)
i.(9 x 7 + 8 x 9 – 15 x 9) : (1 + 3 + 5 + 7 + ........+ 17 + 19)
k.(2 + 4 + 6 + 8 + ... + 20) x (56 x 3 – 72 : 9 x 21)
Tìm X biết a) X + 6 + 327 x 4+X x 3=4647 b) 45:(X+4) x 5+85=150-50
