Tính nhanh :
17 x 12 + 17 x 50 + 17 x 38
Tính nhanh:
11/17 x (38/45 x 17/11)
11/17×646/495
38/45
\(\frac{11}{17}\times\left(\frac{38}{45}\times\frac{17}{11}\right)\)
\(=\frac{11}{17}\times\frac{17}{11}\times\frac{38}{45}\)
\(=1\times\frac{38}{45}\)
\(=\frac{38}{45}\)
\(\frac{11}{17}\times\left(\frac{38}{45}\times\frac{17}{11}\right)\)
\(=\frac{11}{17}\times\frac{38}{45}\times\frac{17}{11}\)
\(=\frac{38}{45}\)
Linz
Tính nhanh:
$\dfrac{11}{17}$ x ( $\dfrac{38}{45}$ x $\dfrac{17}{11}$
Tính nhanh
a,-128.(-25+89)+128(89-125)
b, 15.(17-111)-17.(222+15)
c,-65.(87-17)-87.(17-65)
d,-54+38+12.(-54)-50.(-54)
a, - 128 . (-25+89) + 128.(89-125)
= 128 . - (-25 +89) + 128 . (89 - 125)
= 128 . [-(-25+89)+(89 - 125)]
= 128. (25+89+89-125)
= 128 . (89.2+-100)=128.78=(120+8).(70+8)= 8.190=1520
37/17 + 31/17 < x ≤ 50/18 * 38/25
\(\dfrac{37}{17}+\dfrac{31}{17}< x\le\dfrac{50}{18}.\dfrac{38}{25}\)
\(4< x\le4\dfrac{2}{9}\)
⇒x=∅
Tính nhanh
( 121/122 x 123/125 + 127/129) x ( 1995/1996 x 17/16 - 21/25 : 16/17 ) x ( 42/30 x 75/23 - 19/23 x 210/38)
Bài gì mà lộn xộn vậy trời . Không hiểu gì luôn .
1. Tìm X để có các phân số bằng nhau:
a, 2/3 = 12/ x
b, 14/56 =1/x
c,24/36 = x/12
2. tính nhanh
38/11 + 4/17 - 5/11 - 3/17
3 tính
2/7 x = 2/3
2/5 : x = 1/3
Giúp tui nhanh đc k
1.
a, 2/3=12/x
12/18=12/x
=>x=18
Vậy x=18
b, 14/56=1/x
1/4=1/x
=>x=4
Vậy x=4
c, 24/36=x/12
2/3=x/12
8/12=x/12
=>x=8
Vậy x =8
2
38/11+4/17-5/11-3/17
=(38/11-5/11)+(4/17-3/17)
=33/11+1/17
=3+1/17
=51/17+1/17
=52/17
3.
2/7 x =2/3
x=2/3:2/7
x=2/3x7/2
x=7/3
Vậy x=7/3
2/5:x=1/3
x=2/5:1/3
x=2/5x3
x=6/5
Vậy x= 6/5
K cho mình nha bạn !!!!!!!!!!!!^^
Tớ không hiểu. Cậu giải đi
Tính nhanh:
11 x 12 + 12 x 13 + 13 x 14 + 14 x 15 + 15 x 16 + 16 x 17 + 17 x 18 + 18 x 19 + 19 x 20 + 20 x 21
11 x 12 + 12 x 13 + 13 x 14 + 14 x 15 + 15 x 16 + 16 x 17 + 17 x 18 + 18 x 19 + 19 x 20 + 20 x 21
= 12 x ( 11 + 13 ) + 14 x ( 13 + 15 ) + 16 x ( 15 + 17 ) + 18 x ( 17 + 19 ) + 20 x 21
= 12 x 24 + 14 x 28 + 16 x 32 + 18 x 36 + 420
= 288 + 392 + 512 + 648 + 420
= ( 288 + 392 ) + ( 512 + 648 ) + 420
= 680 + 1160 + 420
= 1840 + 420
= 2260
tk nha
=
Ta có:
11 x 12 + 12 x 13 + 13 x 14 + 14 x 15 + 15 x 16 + 16 x 17 + 17 x 18 + 18 x 19 + 19 x 20 + 20 x 21
= 12 x ( 11 + 13 ) + 14 x ( 13 + 15 ) + 16 x ( 15 + 17 ) + 18 x ( 17 + 19 ) + 20 x 21
= 12 x 24 + 14 x 28 + 16 x 32 + 18 x 36 + 420
= 288 + 392 + 512 + 648 + 420
= ( 288 + 392 ) + ( 512 + 648 ) + 420
= 680 + 1160 + 420
= 1840 + 420
= 2260
#Mạt Mạt#
11 x 12 + 12 x 13 + 13 x 14 + 14 x 15 + 15 x 16 + 16 x 17 + 17 x 18 + 18 x 19 + 19 x 20 + 20 x 21
= 12 x ( 11 + 13 ) + 14 x ( 13 + 15 ) + 16 x ( 15 + 17 ) + 18 x ( 17 + 19 ) + 20 x ( 19 + 21 )
= 12 x 24 + 14 x 28 + 16 x 32 + 18 x 36 + 20 x 40
= 288 + 392 + 512 + 648 + 800
= ( 288 + 392 ) + ( 512 + 648 ) + 800
= 680 + 1160 + 800
= 2640
Tính nhanh:
\(\dfrac{17}{13}:\dfrac{51}{26}=\dfrac{17}{13}x\dfrac{26}{51}=\dfrac{17x13x2}{13x17x3}=\dfrac{2}{3}\)
\(\dfrac{33}{38}:\dfrac{11}{19}\)=?
\(\dfrac{33}{38}:\dfrac{11}{19}=\dfrac{33\times19}{38\times11}=\dfrac{3\times1}{2\times1}=\dfrac{3}{2}\)
Tính nhanh
A)(17/4 x 12/7 - 2/7 x 17/4 - 3/7 x 17/4) x 6/51
B)45 x 16 - 17/ 45 x 15 + 28
a(17/4x12/7-2/7x17/4-3/7x17/4)x6/51
=[17/4x(12/7-2/7-3/7)]x6/51
=17/4x1x6/51
=17/4x6/51
=102/204=1/2
b,45x16-17/45x15+28
=15x3x16-17/45x15+28
=15x48-17/45x15+28
=15x2160/45-17/45x15+28
=15x(2160/45-17/45)+28
=15x2143/45+28
=2143/3+84/3
=2227/3
tính nhanh à,lên google search í
(Người THÀNH CÔNG luôn có một lối đi riêng)