Tính nhanh
17.93+116.83+17.23
19.27+47.81+19.20
87.23+13.93+70.87
78+31+78.24+78.17+22.72
136.23+136.17-40.36
53.39+47.39-53.21-47.21
2.53.12+4.6.87-3.8.40
5.7.77-7.150+49.25+15.42
1.tính nhanh
53.39+47.39+53.21+47.39
2.53.13+4.6.87+3.8.40
5.7.77+7.60+49.25+15.42
53 . 39 + 47 . 39 - 53 . 21 - 47 . 21
= 53 . (39-21) + 47 . (93-21)
=53 . 18 + 47 . 18
= (53 +47) . 18
= 100 .18
=1800
2 . 53 . 12 + 4 . 6 . 87 - 3 . 8 . 40
=24 . 53 + 24 . 87 - 24 . 40
=24 . (53+87-40)
= 24 . 100
= 2400
5 . 7 . 77 - 7 . 60 +49 . 25 -15 . 42.
= 5 . 7 . 77 - 7 . 5 . 12 + 49 . 5 . 5 - 5 . 3 . 42.
= 5 . 539 - 84 . 5 +245 . 5 -5 . 126
= 5 . (539 - 84 + 245 -126)
= 5 . 574
= 2870
Tính nhanh:
a)53.39+47.39-53.21-47.21
b)2.53.12+4.6.87-3.8.40
c)3.7.77-7.60+49.25-15.42
a, 53 x 39 + 47 x 39 - 53 x 21 - 47 x 21
= 53 x (39-21) + 47 x (93-21)
=53 x 18 + 47 x 18
= (53 +47) x 18
= 100 x18
=1800
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,5 x 7 x 77 - 7 x 60 +49 x 25 -15 x 42.
=5 x 7 x 77 - 7 x 5 x 12 +49 x 5 x 5 - 5 x 3 x 42.
=5 x 539 - 84 x 5 +245 x 5 -5 x 126
=5 x (539 - 84 +245 -126)
=5 x 574
=2870
\(a,53\cdot39+47\cdot39-53\cdot21-47\cdot21\)
\(=39\cdot\left(53+47\right)-21\cdot\left(53+47\right)\)
\(=39\cdot100-21\cdot100\)
\(=100\cdot\left(39-21\right)=100\cdot18\)
\(=1800\)
\(b,2\cdot53\cdot12+4\cdot6\cdot87-3\cdot8\cdot40\)
\(=24\cdot53+24\cdot87-24\cdot40\)
\(=24\cdot\left(53+87-40\right)\)
\(=24\cdot100=2400\)
a/39.(53+47)-21.(53-47)
=39.100-21.6
=3900-126
=3774
b);c) tự làm
tính nhanh
a, 53.39+47.39-53.21-47.21
b,2.53.12+4.6.87-3.8.40
c, 5.7.77-7.60+49.25-15.42
a) $53.39+47.39-53.21-47.21$
$=39.(53+47)-21.(53+47)$
$=(39-21).100=18.100=1800$
b) $2.53.12+4.6.87-3.8.40$
$=24.53+24.87-24.40=24.(53+87-40)=24.100=2400$
c) $5.7.77-7.60+49.25-15.42$
$=7.385-7.60+7.175-90.7$
$=7.(385-60+175-90)=7.410=2870$
\(53.39+47.39-53.21-47.21\)
\(=39(47+53)-21(47+53)\)
\(=(39-21)(47+53)\)
\(=18.100=1800\)
\(2.53.12+4.6.87-3.8.40\)
\(=24.53+24.87-24.40\)
\(=24(53+87-40)=24.100=2400\)
\(5.7.77-7.60+49.25-15.42\)
\(=385.7-7.60+7.7.25-15.6.7\)
\(=385.7-7.60+7.175-7.90\)
\(=7(385-60+175-90)=7.410=2870\)
a, 53.39+47.39-53.21-47.21
=39.(53+47)-21.(53+47)
=39.100-21.100
=100.(39-21)
=100.18
=1800
b,b,2.53.12+4.6.87-3.8.40
=24.53+24.87-24.40
=24.(53+87-40)
=24.100
=2400
c,5.7.77-7.60+49.25-15.42
=7.385-7.60+7.175-90.7
=7.(385-60+175-90)
=7.410
=2870
Chúc bạn học tốt
Tính
53 . 39 + 47.39 +53.21+47.21
2.53.12+ 4.6.87 - 3. 8 .40
5.7.77 - 7.60 + 49.25 - 15.42
Ai làm nhanh mình tick nhé
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 40
= 4000
2 x 53 x 12 + 4 x 6 x 87 - 3 x 8 x 40
= 1272 + 2088 - 960
= 3360 - 960
= 2400
5 x 7 x 77 - 7 x 60 + 49 x 25 - 15 x 42
= 2695 - 420 + 1225 - 630
= 2275 + 595
= 2870
Học tốt!!!
Bài 7: Tính nhanh: a) 136.23 + 136.17 – 40.36 b) 17.93 + 116.83 + 17.23 b) 19.27 + 47.81 + 19.20 c) 87.23 + 13.93 + 70.87
a) \(136.23+136.17-40.36\)
\(=136.\left(23+17\right)-40.36\)
\(=136.40-40.36\)
\(=40\left(136+36\right)\)
\(=40.172\)
\(=6880\)
Tính nhanh
a,53.39 + 47.39 - 53.21 - 47.21
b, 2.53.12 + 4.6.87 - 3.8.40
c, 5.7.77 - 7.60 + 49.25 - 15.42
a, = ( 53 + 47 ) . 39 - ( 53 + 47 ) . 21
= 100 . 39 - 100 . 21
= 100 . ( 39 - 21 )
= 100 .18
= 1800
b, = 24 . 53 + 24 . 87 - 24 . 40
= 24 . ( 53 + 87 - 40 )
= 24 . 100
= 2400
c, = 5.7.77 - 7.60 + 7.7.25 - 15 . 7 .6
= 7 . ( 5 .77 - 60 + 7 . 25 - 15 . 6 )
= 7 . ( 385 - 60 + 175 - 90 )
= 7. 410
= 2870
dấu chấm trong bài là dấu phẩy hay dấu nhân
bạn lê phan joly
....
136.23 + 136.17 – 40.36
l) 17.93 + 116.83 + 17.23
m) 19.27 + 47.81 + 19.20
n) 87.23 + 13.93 + 70.87
136.23 + 136.17 – 40.36
l) 17.93 + 116.83 + 17.23
m) 19.27 + 47.81 + 19.20
n) 87.23 + 13.93 + 70.87
hãy giúp mình
tính nhanh
53.39+47.39+53.21+47.21
2.53.12+4.6.87 -3.8.40
5.7.77-7.60+49.25-12.42