Tính nhanh
a) 2 . 31 . 12 + 4 . 6 . 42 + 8 . 27 . 3
b) 36 . 28 + 36 . 82 + 64 . 69 + 64 . 41
Tính nhanh
a) 2 . 31 . 12 + 4 . 6 . 42 + 8 . 27 . 3
b) 36 . 28 + 36 . 82 + 64 . 69 + 64 . 41
mik đầu tiên nhé bạn !
a) 2.31.12+4.6.42+8.27.3
=24.31+24.42+24.27
=24.(31+42+27)
=24.100
=2400
b) 36.28+36.82+64.69+64.41
=36.(28+82)+64.(69+41)
=36.110+64.110
=110.(36+64)
=110.100
=11000
Tính nhanh:
a) 2 . 31 . 12 + 4 . 6 . 42 + 8 . 27 . 3
b) 36 . 28 + 36 . 82 + 64 . 69 + 64 . 41
a) 2 . 31 . 12 + 4 . 6 . 42 + 8 . 27 . 3
= 24 . 31 + 24 . 42 + 24 . 27
= 24 . (31 + 42 + 27)
= 24 . 100
= 2400
b) 36 . 28 + 36 . 82 + 64 . 69 + 64 . 41
= 36 . (28 + 82) + 64 . (69 + 41)
= 36 . 110 + 64 . 110
= (36 + 64) . 110
= 100 . 110
= 11000
Tính nhanh
a , 2 . 31 . 12 + 4 . 6 . 42 + 8 . 27 . 3
b, 36 . 28 + 36 . 82 + 64 . 69 + 64 . 41
a) 2.31.12+4.6.42+8.27.3
=24.31+24.42+24.27
=24.(31+42+27)
=24.100
=2400
b) 36.28+36.82+64.69+64.41
=36.(28+82)+64.(69+41)
=36.110+64.110
=110.(36+64)
=110.100
=11000
a = 24 . 31 + 24 . 42 + 24 . 27
= 24 . 100
= 2400
b = 36 . ( 28 + 82 ) + 64 . ( 69 + 41 )
= 36 . 110 + 64 . 110
= 110 . ( 36 + 64 )
= 100 . 100 = 11000
a = 24 . 31 + 24 . 42 + 24 . 27
= 24 . 100
= 2400
b = 36 . ( 28 + 82 ) + 64 . ( 69 + 41 )
= 36 . 110 + 64 . 110
= 110 . ( 36 + 64 )
= 110 . 100 = 11000
a) 2 . 31 . 12 + 4 . 6 . 42 + 8 . 27 . 3
b) 36 . 28 + 36 . 82 + 64 . 69 . 64 . 41
b) 36.28+36.82+64.69+64.41
= 36.(28+82)+64.(69+41)
=36.110+64.110
=(36+64).110
=100.110
=11000.( phần a mk nghĩ sau )
b) = 36 . (28+82) + 64 . (69+41)
= 36 . 110 + 64 . 110
= (36+64) . 110
= 100 . 110
= 11000
a, 2 . 31 . 12 + 4 . 6 . 42 + 8 . 27 . 3
= 2 . 31 . 3 . 4 + 4 . 2 .3 . 42 + 2 . 4 . 27 . 3
= 2 . 3 . 4 ( 31 + 42 + 27 )
= 2 . 3 . 4 . 110
= 2640
tính nhanh : a ) 2 x 31 x 12 + 4 x 6 x 42 + 8 x 27 x 3 b ) 36 x 28 + 36 x 82 + 64 x 69 + 64 x 41
tính nhanh
a) 2 . 31 . 12 + 4 . 6 . 42 + 8 . 27 . 3
b) 36 . 28 + 36 . 82 + 64 . 69 + 64 . 41
ai nhanh và đúng mình like
a) 2.31.12+4.6.42+8.27.3
= [(2.12).31]+[(4.6).42]+[(8.3).27]
= 24.31+24.42+24.27
= 24.(31+42+27)
= 24.100
= 2400
b) 36.28+36.82+64.69+64.41
= (36.28+36.82)+(64.69+64.41)
= [36.(28+82)]+[64.(69+41]
= 36.110+54.110
= 110.(36+54)
= 110.90
= 200
a) 2 . 31 .12 + 4 .6 .42 + 8 .27 .3
= 2 .12 .31 + 4 . 6 .42 + 8 . 3 .27
= 24 . 12 + 24 . 42 + 24 . 27
= 24 . ( 12 + 42 + 27 )
= 24 . 86
= 2064
b) 36 . 28 + 36 . 82 + 64 . 69 + 64 . 41
= 36. ( 28 + 82 ) + 64 . ( 69 + 41 )
= 36 . 110 + 64 . 110
= ( 36 + 64 ) . 110
= 100 . 110
= 11000
tính nhanh
a) 2 . 31 . 12 + 4 . 6 . 42 + 8 . 27 . 3
b) 36 . 28 + 36 . 82 + 64 . 69 + 64 . 41
a) 2.31.12+4.6.42+8.27.3
= [(2.12).31]+[(4.6).42]+[(8.3).27]
= 24.31+24.42+24.27
= 24.(31+42+27)
= 24.100
= 2400
b) 36.28+36.82+64.69+64.41
= (36.28+36.82)+(64.69+64.41)
= [36.(28+82)]+[64.(69+41]
= 36.110+54.110
= 110.(36+54)
= 110.90
= 200
56 . Tính nhanh :
a ) 2 x 31 x 12 + 4 x 6 x 42 + 8 x 27 x 3
b ) 36 x 28 + 36 x 82 + 64 x 69 + 64 x 41
a) 2 x 31 x 12 + 4 x 6 x 42 + 8 x 27 x 3
= 24 x 31 + 24 x 42 + 24 x 27
= 21 x ( 31 + 42 + 27)
= 21 x 100
= 2100
b) 36 x 28 + 36 x 82 + 64 x 69 + 64 x 41
= 36 x ( 28 + 82) + 64 x ( 69 + 41)
= 36 x 110 + 64 x 110
= 110 x ( 36 + 64)
= 110 x 100
= 11000
a)2 x 31 x12 + 4 x 6 x 42 + 8 x 27 x 3
= 24 x 31 + 24 x 42 + 24 x 27
= 24 x (31 + 24 + 27)
=24 x 82
=1968
b)36 x 28 + 36 x 82 + 64 x 69 + 64 x 41
=36 x (28 + 82) + 64 x ( 69 + 41 )
=36 x 110 + 64 x 110
=3960 + 7040
=11000
a) 2x31x12+4x6x42+8x27x3
=2x12x31+4x6x42+8x3x27
=24x31+24x42+24x27
=24x(31+42+27)
24x100=2400
b)36x28+36x82+64x69+64x41
=36x(28+82)+64x(69+41)
=36x110+64x110
Tính nhanh 2 biểu thức sau:
a) 2 x 31 x 12 +4 x 6 x 42 + 8 x 27 x 3
b) 36 x 28 + 36 x 82 + 64 x 69 + 64 x 41
2 x 31 x 12+ 4 x 6 x 42 + 8 x 3 x 27 = 24 x 31 + 24 x 42 + 24 x 27 = 24 x (27 + 31 + 42) = 24 x 100 = 2400
b) 36 x 28 + 36 x 82 + 64 x 69 + 64 x 41 = 36 x (28 + 82) + 64 x (69 + 41) = 36 x 110 + 64 x 110 = 110 x (64 + 36) = 110 x 100 = 11000
A) 2 ×31×12+4×6×42+8×27×3
B) 36×28+36×82+64×69+64×41
C) Tính tổng : S=1+2+3+4.......+99+100
Giúp mình với
A) 2x31x12+4x6x42+8x27x3
= 2x12x31+4x6x42+8x3x27
=24x31+24x42+24x27
=24x(31+42+27)
=24x100
=2400
B)36x28+36x82+64x69+64x41
= 36x(28+82) + 64x(69+41)
= 36x110 + 64x110
= 110x (36+64)
= 110x 100
= 11000
C) Số các số hạng của S là : (100 - 1) / 1 + 1 = 100 (số)
Tổng S = (100+1)x100/2 = 5050