Tính nhanh : 25×5+19×2×4
Tính nhanh :25×5+19×2×4
\(25.5+19.2.4=\left(20+5\right).5+\left(10+9\right).8\)
\(=20.5+5.5+10.8+9.8=100+25+80+72=277\)
(Bảo đảm kết quả này đúng, click cho tớ với nhá!)
Tính nhanh
a. 5/11 + 1/4 + 2/5 + 6/11 + 3/4 + 6/25 + 9/25
b. 19/4 + 37/100 + 1/8 + 1/2 + 163/100 + 3/8
a.
(5/11 + 6/11 ) + ( 1/4 +3/4) + ( 6/25 + 9/25)
= 11/11 + 4/4 + 15/25
= 1 +1 + 3/5
= 2+3/5 = 13/5
b.
( 37/100 + 163/100) + (1/8 + 3/8 ) + 19/4 + 1/2
= 200/100 + 4/8 + ( 19/4 + 2/4)
= 2 + 1/2 + 21/4
= 31/4
19/4+37/100+1/8+132/25+5/2+37/12
tính nhanh hộ mình với
4750/1000 + 370/1000 + 5280/1000 + 2500/1000 + 37/12 = 129/10 + 37/12 = 959/60
Bài 1: Tính nhanh
a, 5/11 + 1/2 + 2/5 + 6/11 + 3/4 + 16/25 + 5/16
b,19/4 + 37/100 + 1/8 + 132/25 + 5/2 + 37/12
c, 1313/1313 * 165165/143143 * 424242/151515
d, (121/122 * 123/125 + 127/129) * (1995/1996 * 17/16 - 21/25 : 16/17) * (42/30 * 75/23 - 19/23 * 210/38)
tính nhanh
a) 30/4-6/8-15/20
b)12/9x15/10
c)12/25:2/5
d) 16/17x12/19+16/17x7/19
a) 30/4 - 6/8 - 15/20 = 30/4 - 3/2 = 6
tính nhanh:
19/4 + 37/100 + 1/8 +1/2 + 163/4 + 6/25 + 9/25
19/4 + 37/100 + 1/8 + 1/2 + 163/4 + 6/25 + 9/25
=( 19/4 + 163/4 )+ 37/100 + (1/8 + 1/2 ) + ( 6/25 + 9/25 )
= 182/4 +37/100+5/8+3/5
=(182/4+37/100+3/5)+5/8
=(4550/100+37/100+60/100)+5/8
=4647/100+5/8
=9419/200
Tìm x :
a) x . ( x - 2 ) = 0
b) ( x - 1 ) . ( x - 3 ) = 2
Tính nhanh ( nếu có )
a) 15 . 37 .4 + 120 . 21 + 21 . 5 . 12
b) 19 + 19 . 99 - 25 . 8
c) 27 + 73 - 30 : ( 25 - 10 )
d) 15 - 25 . 8 : ( 25 - 10 )
\(x\left(x-2\right)=0\)
\(\Rightarrow\orbr{\begin{cases}x=0\\x-2=0\end{cases}}\)
\(\Rightarrow\orbr{\begin{cases}x=0\\x=2\end{cases}}\)
1. Tính nhanh
A, 32684 + 41325 + 316 + 675
B, 25 x 18 x 4 x 2
C, 19 x 81 + 19 + 18 x 19
giúp với =)
a, 32684 + 41325 + 316 + 675
= (32684 + 316) + (41325 + 675)
= 33 000 + 42 000
= 75 000
b, 25 \(\times\) 18 \(\times\) 4 \(\times\) 2
= (25 \(\times\) 4) \(\times\) (18 \(\times\) 2)
= 100 \(\times\) 36
= 3600
c, 19 \(\times\) 81 + 19 + 18 \(\times\) 19
= 19 \({}\) \(\times\) 81 + 19 \(\times\) 1 + 18 \(\times\) 19
= 19 \(\times\) (81 + 1 + 18)
= 19 \(\times\) 100
= 1900
tính nhanh
4+7+10+13+16+19+5+9+13+17+21+25
[25+5] + [19+21] + [13+7] + [4+16] + [17+13] + [10+9]
30+40+20+20+40+19
150+19
169
đúng ko
a] [4+16]+[7+13]+[19+21]+[5+25]+[13+17]+[10+19]
= 20+20+40+30+30+29
=169