tính nhanh
a,(2100-42):21
b, 2*31*12+4*6*42+8*27*3
tính nhanh:2*31*12+4*6*42+8*27*3
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
2*31*12+4*6*42+8*27*3
=24*31+24*42+24*27
=24*[31+42+27]
=24*100
=2400
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 ( 31 + 42 + 27 )
= 24 x 100
= 2400
tính nhanh 2*31*12+4*6*42+8*27*3
ai nhanh sẽ t
2*31*12+4*6*42+8*27*3
=(2*12)*31+(6*4)*42+(8*3)*27
=24*31+24*42+24*27
=24*(31+42+27)
=24*100
=2400
2 x 31 x 12 + 4 x 6 x 42 + 8 x 27 x 3
= (2 x 12) x 31 + (6 x 4) x 42 + (8 x 3) x 27
= 24 x 31 + 24 x 42 + 24 x 27
= 24 x (31 + 42 + 27)
= 24 x 100
= 2400
Tính nhanh :
2 x 31 x 12 + 4 x 6 x 42 + 8 x 27 x 3
2 x 31 x 12 + 4 x 6 x 42 + 8 x 27 x 3
= 2 x 31 x 4 x 3 + 4 x 2 x 3 x 42 + 2 x 4 x 3 x 27
= [2 x 3 x 4] x (31 + 42 + 27)
= 24 x 100
= 2400
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 . 83 + 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+36.83+64.69+64.41
=36.(28+83)+64.(69+41)
=36.111+64.111
=(36+64).111
=100.111
=11100
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
Tính nhanh:
a, 2 x 31 x 12 + 4 x 6 x 42 + 8 x 27 x3
b, 2 x 53 x 12 + 4 x 6 x 87 -3 x 8 x 40
c, 5 x 7 x 77 -7 x 60 + 49 x 25 - 15 x 42
a, 2 x 31 x 12 + 4 x 6 x 42 + 8 x 27 x 3
= 2 x 12 x 31 + 4 x 6 x 42 + 8 x 3 x 27
= 24 x 31 + 24 x 42 + 24 x 27
= 24 x ( 31 + 24 + 27 )
= 24 x 82
= 1968
b, 2 x 53 x 12 + 4 x 6 x 87 - 3 x 8 x 40
= 24 x 53 + 24 x 87 - 24 x 40
= 24 x ( 53 + 87 - 40 )
= 24 x 100
= 2400
c, Tương tự
a) 2 x 31 x 12 + 4 x 6 x 42 + 8 x 27 x 3
= 2 x 12 x 31 + 4 X 6 x 42 + 8 x 3 x27
=24 x 31 + 24 x 42 + 24 x 27
= 24 x ( 31 + 24 + 27 )
= 24 x 82
=1968
Tính nhanh:
2 x 31 x 12 + 4 x 6 x 42 + 8 x 27 x 3
2 x 31 x 12 + 4 x 6 x 42 + 8 x 27 x 3 =( 2 x 12) x 31 + (4 x 6) x 42 +( 8 x 3) x 27
= 24 x 31 + 24 x 42 + 24 x 27
= 24( 31+42+27)
=24 x100
=2400
\(2\cdot31\cdot12+4\cdot6\cdot42+8\cdot27\cdot3\)
\(=\left(2\cdot12\right)\cdot31+\left(4\cdot6\right)\cdot42+\left(8\cdot3\right)\cdot27\)
\(=24\cdot31+24\cdot42+24\cdot27\)
\(=24\cdot\left(31+42+27\right)\)
\(=24\cdot100\)
\(=2400\)
dấu . là đấu nhân nha!!
2x31x12+4x6x42+8x27x3
=62x12+24x42+216x3
=62x3x4+3x8x42+216x3
=248x3+3x336+216x3
=3x(248+336+216)
=3x800
=2400