tính nhanh
15.37.4+120.21+21.5.12 ?
2,Tính nhanh
15.37.4 + 120.21 + 21.5.12
dấm . là dấu nhân,mik vt tắt
5.3.37.4+5.24.21+21.5.12
= 5.(3.37.4+24.21+21.12)
= 5.1200
= 6000
15.37.4 + 120.21 + 21.5.12
= (15 .4) . 37 + 60 . 2 . 21 + (12 . 5) . 21
= 60 . 37 + 60 . 42 + 60 . 21
= 60 . (37 + 42 + 21)
= 60 . 100
= 6000
15 . 37 . 4 + 120 . 21 + 21 . 5 . 12
= 15 . 4 . 37 + 21 ( 120 + 5 . 12 )
= 60 . 37 + 21 ( 120 + 60 )
= 2220 + 21 . 180
= 2220 + 3780
= 6000
tính nhanh 15.37.4+120.21+21.5.12
5.3.37.4+5.24.21+21.5.12
= 5.(3.37.4+24.21+21.12)
= 5.1200
= 6000
tính nhanh
15.37.4 + 120.21 + 21.5.12
= ( 37 - 15 ) .4 ( vì ở phép nào cũng có số 21 ) + 120 .21 + 21 . 5 . 12
= 21 . 4 + 120 . 21 + 21 . 5.12
= 21 . ( 4 + 120 + 12 )
= 21. 136
= 2 856
mk nghĩ thế
Đề bài: Tính nhanh
15.37.4+120.21+21.5.12
15.37.4 + 120.21 + 21.5.12 = 15.4.37 + 21.2.60 + 5.12.21 = 60.37 + 42.60 + 60.21 = 60.(37 + 42 + 21) = 60.100 = 6000
37.4+120.21+21.5.12
37.4 + 120.21 + 21.5.12
= 148 + 21.( 120 + 60)
= 148+ 21 . 180
= 148 + 3780
= 3928
\(37.4+120.21+21.5.12\\ =37.4+120.21+21.60\\ =37.4+120.21+21.60\\ =37.4+\left(120+60\right).21\\ =37.4+180.21\\ =37.4+4.45.21\\ =37.4+4.945\\ =\left(37+945\right).4\\ =982.4=3928\)
c)15.37.4+120.21+21.5.12
`15*37*4+120*21+21*5*12`
`=60*37+60*2*21+60*21`
`=60(37+42+21)`
`=60*100`
`=6000`
Làm hộ mik vs
15.37.4+120.21+21.5.12 ?
15 . 37 .4 + 120 . 21 + 21 . 5 . 12
⇒( 15 . 4 ) . 37 + 60 . 2 . 21 + ( 12 . 5 ) .21
⇒60 . 37 + 60 . 42 + 60 . 21
⇒60 . ( 37 + 42 + 21 )
⇒60 . 100
⇒6 000
tinh nhanh 15.37.4+120.21+21.5.12
=(15.4).37+60.2.21+(12.5).21
=60.37+60.42+60.21
=60.(37+42+21)
=60.100
=6000
= 15 . 37 . 4 + 15 . 8 + 3 . 7 + 3 .7 . 5 . 12
= 15 . 37 . 4 + 15 . 8 + 3 . 7 + 15 . 7 . 12
= 15 . (37 . 4 + 8 + 3 . 7 + 7 . 12)
= 15 . 261
= 3915
tick đúng cho tớ nhé !
Tính một cách hợp lí
a) 13.58.4+32.26.2+52.10
b)14.35.5+10.25.7+20.70
C) 15.(27+18+6)+15.(23+12)
d) 53.(51+4)+53.(49+96)+53
e)15.37.4+120.21+21.5.12
a) \(\text{13 x 58 x 4 + 32 x 26 x 2 + 52 x 10 }\)
\(\text{=(13 x 4 ) x 58 + 32 x 13 x 2 x 2 + 13 x 4 x 10}\)
\(\text{= ( 13 x 4 ) x 58 + 32 x ( 13 x 2 x 2 ) + ( 13 x 4 ) x 10 }\)
\(\text{= 52 x 58 + 32 x 52 + 52 x 10}\)
\(\text{=52 x ( 58 + 32 + 10 )}\)
\(\text{=52 x 100 = 5200}\)
b) \(\text{14 x 35 x 5 + 10 x 25 x 7 + 20 x 70 x 2}\)
\(\text{= ( 14 x 5 ) x 35 + (10 x 7 ) x 25 + 20 x 70 x 2 }\)
\(\text{= 70 x 35 + 70 x 25 + 20 x 2 x 70 }\)
\(\text{= 70 x ( 35 + 25 + 40 )}\)
\(\text{= 70 x 100 = 7000 }\)
e) \(\text{5.3.37.4+5.24.21+21.5.12}\)
\(\text{= 5.(3.37.4+24.21+21.12)}\)
\(\text{= 5.1200}\)
\(=6000\)
a) \(13.58.4+32.26.2+52.10\)
\(=52.58+32.52+52.10\)
\(=52.\left(58+32+10\right)\)
\(=52.100=5200\)
b) \(14.35.5+10.25.7+20.70\)
\(=7.5.35.2+10.7.25+20.70\)
\(=35.70+70.25+20.70\)
\(=70\left(35+25+20\right)\)
\(=70.80=5600\)
c) \(...=15\left(27+18+6+23+12\right)\)
\(=15\left(27+23+18+12+6\right)\)
\(=15\left(50+30+6\right)=15.86=1290\)
d) \(...=53\left(51+4+49+96+1\right)\)
\(=53\left(51+49+4+96+1\right)\)
\(=53\left(100+100+1\right)=53.201=10653\)
e) \(15.37.4+120.21+21.5.12\)
\(=15.4.37+60.2.21+21.60\)
\(=60.37+60.42+21.60\)
\(=60.\left(37+42+21\right)=60.100=6000\)