53 * 39 + 43 * 39 – 53 * 21 – 47 * 21
tính nhanh a / 166 * ( – 127 + 234 ) – 234 * ( 166 +127 )
b / 53 * 39 + 43 * 39 – 53 * 21 – 47 * 21
a) 166.(-127)+166.234+(-234).166-234.127
166.(-234+234)+127.(-166-234)
=0+127.(-400)
=-50800
b) 53.39+43.39-53.21-47.21
=39.(53+43)+(-21).(53+47)
=39.96+(-21).100
=-1644
k cho minh
53 . 39 + 47 . 39 - 53 . 21 - 47 .21
= 39 . ( 53 + 47 ) - 21 . ( 53 + 47 ) = 39 . 100 - 21 . 100 = 100 . ( 39 - 21 ) = 100 . 18 = 1800
53*39+47*39-53*21-47*21
53*39+47*39-53*21-47*21
\(=39x\left(53+47\right)-\left(21x\left(53+47\right)\right)\)
\(=39x100-21x100\)
\(=100x\left(39-21\right)\)
\(=18x100=1800\)
53*39 +47*39 -53*21-47*21
\(53.39+47.39-53.21-47.21\)
\(=53\left(39-21\right)+47\left(39-21\right)\)
\(=\left(39-21\right)\left(53+47\right)\)
\(=18.100=1800\)
Tính nhanh
53*39+47*39-53*21-47*21
53 x 39 + 47 x 39 - 53 x 21 - 47 x 21
= 39 x ( 53 + 47 ) - 21 x ( 53 + 47 )
= 39 x 100 - 21 x 100
= 100 x ( 39 - 21 )
= 100 x 18
= 1800
53 x 39 + 47 x 39 - 53 x 21 - 47 x 21
= 39 x ( 53 + 47 ) - 21 x ( 53 + 47 )
= 39 x 100 - 21 x 100
= 100 x ( 39 - 21 )
= 100 x 18
= 1800
ai k mik k lai
53 x 39 + 47 x 39 - 53 x 21 - 47 x 21
= 39 x ( 53 + 47 ) - 21 x ( 53 + 47 )
= 39 x 100 - 21 x 100
= 100 x ( 39 - 21 )
= 100 x 18
= 1800
53 .39 + 47 . 39 - 53 . 21 - 47 .21 tính nhanh
53 .39 + 47 . 39 - 53 . 21 - 47 .21
= (53 + 47) . 39 - (53 + 47) . 21
= 100 . 39 - 100 . 21
= 100 . (39 - 21)
= 100 . 18
= 1800
53 . 39 + 47 . 39-53 .21 - 47 . 21
= 39. (53 + 47 ) - 21. ( 53 -47)
=39 . 100 - 21 . 6
= 3900 -126
=3774
\(53.39+47.39-53.21-47.21\)
\(=39.\left(47+53\right)-\left(53-47\right).21\)
\(=39.100-6.21\)
\(=3.13.100-2.3.21\)
\(=3.\left(1300-42\right)\)
\(=3.1258\)
\(=3774\)
tính nhanh
53 + 39 + 47 x 39 - 53 x 21 - 47 x 21
Tính nhanh
53 x 39 + 47 x 39 - 53 x 21 - 47 x 21
tính nhanh 210+47*4+16*47
53 . 39 + 47 . 39 - 53 . 21 - 47 . 24
sửa chỗ sai của bạn lại: 53.39+47.39-53.21-47.21
= (53+47).(39-21)
=100.18
=1800
Đáp án đúng là 4200 đấy mk lm r
K nhá