\(x:\dfrac{2}{5}=\dfrac{7}{13}\)
\(x=\dfrac{7}{13}\times\dfrac{2}{5}\)
\(x=\dfrac{14}{65}\)
x : 2/5 = 7/13
x = 7/13 x 2/5
x = 14/65
Vậy x = 14/65
Tính bằng cách thuận tiên nhất:
1):(3/4 x 5/97 + 1/9 x 13/47) x (1/5 - 7/25 x 5/7)
2): 8/17 x 4/15 + 8/17 x 22/15 - 8/15 x 9/17
3): 2021/2 x 1/3 + 4042/4 x 1/5 + 6063/3 x 22/15
4); 4/7 x 2/13 + 8/13 :7/4 + 4/7 : 13/2 + 4/7 x 1/13
5): 2022 x 2021 - 1/ 2021 + 2022 x 2020
6): 18 x 123 + 9 x 4567 x 2 + 3 x 5310 x 6 / (2 + 4 + 6 + 8 + ...+20 + 22) + 48
7): A= 2021 x 2021 x 202020 - 2020 x 2020 x 20212021 / 2020 x 20192019
tính nhanh
a) 12/13 + 2/7 + 8/13 + 6/13 + 5/7 =
b) (1 - 1/2) x (1 - 1/3) x ( 1 - 1/4) x (1 - 1/5) =
a) X + = 4/5 : 2/3 b) 4/7 x 8/13 + 8/13 x 3/7
1 tim x
Ai nhanh to k
x x - 4/7 = 15/20
x x 2/7 -2/3 =1/2
x : 5/4 + 4/5 =2
2 tinh
4/3 x 7/8 x 5
8/9 x 6/5 x 2/3
4/7 : 5/7 x 10/11
8/13 : 7/13 : 4
dung hay sai
5/7 + 3/4 = 41/28 ........
3 + 2/5 = 1........
11/9 - 5/6 = 7/18.......
4 - 3/7 = 25/7.....
tim x
x + 4/11 =3/5
a 13/3 b 13/11 c 13/55 d 13/31
a ( 3/4 + 1/2 ) x 5/7 =
Tính bằng hai cách:
Cách 1 :
Cách 2 :
b) 5/7 x 13/21 + 2/7 x 13/ 21=
Tính bằng hai cách :
Cách 1 :
Cách 2 :
c) Tính 7/5 + 4/3 + 7/5 + 4/3 bằng hai cách :
Cách 1 : 7/5 + 4/3 + 7/5 + 4/3 = 7/5 x 2 + 4/3 x 2 =
Cách 2 : 7/5 + 4/3 + 7/5 + 4/3 = ( 7/5 + 4/3) x 2 =
tính nhanh
4/5-2/3/+1/5-1/3
2/5 x 7/4 - 2/5x3/7
13/4 x 2/3 x 4/13 x 3/12
75/100 + 18/21 + 19/32 +1/4 + 3/21 + 13/32
2/5 + 6/9+3/4+3/5+1/3+1/4
5/7 x 13/21 + 2/7 x 13/21
Nhớ là tính bằng 2 cách nha
Bài 4: Rút gọn rồi tính
A. 5/3 x 4/5
B. 2/3 x 3/7
C. 7/13 x 13/7
Tìm x :
X + 5/9 = 4/3 X - 4/9 = 1/2 6/13 + X = 7/6 13/5 - X = 5/6
Giúp mình ạ !
