`#040911`

`a)`

`27 \times 38 + 62 \times 27 - 27 \times 90`

`= 27 \times (38 + 62 - 90)`

`= 27 \times (100 - 90)`

`= 27 \times 10`

`= 270`

\(27\times38+62\times27-27\times90\)

\(=27\times\left(38+62-90\right)\)

\(=27\times\left(100-90\right)\)

\(=27\times10\)

\(=270\)

=(38+62)*27+(37+90)

=100*27+127

=2700+127=2827

27 x 38 + 62 x 37 + 27 x 90

\(=27\times\left(38+90\right)+62\times37\)

\(=27\times128+62\times37\)

\(=4356+2294\)

\(=6650\)

27×38+62×37+27×90

=27×(38+90)+62×37

=27×128+62×37

=4356+2294

=6650

Ta có:

49 x 62 + 38 x 73 + 31 x 51 x 2 + 19 x 27 x 2

= 49 x 62 + 38 x 73 + 62 x 51 + 38 x 27

= 62 x ( 49 + 51 ) + 38 x ( 73 + 27 )

= 62 x 100 + 38 x 100

= ( 38 + 62 ) x 100

= 100 x 100

= 10 000

49x62+38x73+31x51x2+19x27x2

= 3038+2774+3162+1026

=10000

k cho mk nha bn!                    :)

tính nhanh thủy ạ

62+27x38=62+1026
                =1088

= 1088

hok tốt

= 62+1026

=1088

hok tốt

9: =3/2*5/12+3/16

=15/24+3/16

=5/8+3/16

=13/16

\(a)9.4.25.8.125\)

\(=9.\left(4.25\right).\left(8.125\right)\)

\(=9.100.1000\)

\(=900.1000\)

\(=900000\)

\(a,9.4.25.8.125=9.\left(4.25\right).\left(8.125\right)=9.100.1000=900000\)

\(b,25.5.27.2\)(câu này hình như thiếu đề, ko tính nhanh đc)

\(c,37.7+80.3+43.7\)\(=7.\left(37+43\right)+80.3\)\(=7.80+3.80=80\left(7+3\right)=80.10=800\)

\(d,113.38+113.62+87.62+87.38\)\(=113\left(38+62\right)+87\left(62+38\right)\)

\(=113.100+87.100=100.\left(113+87\right)=100.200=20000\)

Viết gọn lũy thừa:

\(a,x.x.y.y.x.y.x=\left(x.x.x.x\right).\left(y.y.y\right)=x^4.y^4\)

\(b,7^5:343=7^5:7^3=7^{5-3}=7^2\)

\(c,A^{12}:A^{18}=A^{12-18}=A^{-6}\)

\(d,x^7.x^4.x=x^{7+4+1}=x^{12}\)

\(\left(56.27+56.35\right):62=56\left(27+35\right):62=56.62:62=56\)

\(\left(56.27+56.35\right):62\)

\(=\left[56.\left(27+35\right)\right]:62\)

\(=56.62:62\)

\(=56.1\)

\(=56\)

\(\left(56\times27+56\times35\right):62\)

\(=56\times\left(27+35\right):62\)

\(=56\times62:62\)

\(=56\)

HOK TOT