B= 16 2\7:(-3\5)- 28 2\7:(-3\5)
a) 4/7.|x|+1/28=12/28
b)16/2/7:(-3/5)-26/2/7:(-/5)
Câu b 16/2/7 và 26/2/7 là hỗn số nha
Thanks
16 2/7 : (-3/5) + 28 2/7 : 3/5
\(16\frac{2}{7}\):\(\left(\frac{-3}{5}\right)\)+ \(28\frac{2}{7}\):\(\frac{3}{5}\)
= \(-16\frac{2}{7}\):\(\frac{3}{5}\)+\(28\frac{2}{7}\):\(\frac{3}{5}\)
=(\(-16\frac{2}{7}\)+\(28\frac{2}{7}\)) : \(\frac{3}{5}\)
=12 : \(\frac{3}{5}\)=12.\(\frac{5}{3}\)=20
\(16\dfrac{2}{7}:\left(\dfrac{-3}{5}\right)+28\dfrac{2}{7}:\dfrac{3}{5}\)
\(16\dfrac{2}{7}:\left(\dfrac{-3}{5}\right)+28\dfrac{2}{7}:\dfrac{3}{5}\)
\(=\left(-16-\dfrac{2}{7}+28+\dfrac{2}{7}\right)\cdot\dfrac{5}{3}\)
\(=12\cdot\dfrac{5}{3}=20\)
6) \(16\dfrac{2}{7}:\left(\dfrac{-3}{5}\right)+28\dfrac{2}{7}:\dfrac{3}{5}\)
\(16\dfrac{2}{7}:\left(\dfrac{-3}{5}\right)+28\dfrac{2}{7}:\dfrac{3}{5}\)
\(=\left(-16-\dfrac{2}{7}\right)\cdot\dfrac{5}{3}+\left(28+\dfrac{2}{7}\right)\cdot\dfrac{5}{3}\)
\(=12\cdot\dfrac{5}{3}=20\)
quy đồng mẫu số
a 7\4 15\16 b 1\8 2\3 và 5\2
c 2\7 9\4 và 5\28
a: 7/4=28/16
15/16=15/16
b: 1/8=3/24
2/3=16/24
5/2=60/24
c: 2/7=8/28
9/4=63/28
5/28=5/28
a)\(28/16 và 15/16\)
b)\(3/24; 16/24; 60/24\)
c)\(8/28; 63/28; 5/28\)nhé
tính bằng cách hợp lí nếu có thể
a 5/7 x 9/11 + 5/7 x 2/11 - 5/7
b 15/35 + ( 16/28 - 7/35 ) + 12/15
c 15/35 + 16/28 - 7/35 - 12/15
d 3/1/4 x ( 1/1/2 - 1 ) + 2,5 - 1/2 )
A =15/34 + 7/21 + 9/34 - 1 15/17 + 2/3
B = 16 2/7 : ( - 3/5 ) - 28 2/7 : ( - 3/5 )
C = 25.(- 1/3) 3 + 1/5 - 2.( - 1/2 )2 -1/2
D = ( - 2 )3 . ( 3/4 - 0,25 ) : ( 2 1/4 - 1 1/6 )
F = ( - 3/2 )2 + |- 5/6 | - 1 1/2 : 6
I = - 1,53 : ( 5 5/28 - 1 8/9 .1,25 + 1 16/63 )
Thực hiện phép tính
A (1+ 2/3 - 1/4) . (0,8 - 3/4)2
b) 16 2/7 : (-3/5) + 28 2/7 : 3/5
Tìm x:
a) \(\dfrac{-3}{7}\).x=\(\dfrac{3}{56}\).\(\dfrac{28}{9}\)
b) x-\(\dfrac{3}{16}\)=\(\dfrac{7}{15}\):\(\dfrac{3}{5}\)
c) \(\dfrac{2}{5}\)+\(\dfrac{1}{5}\).x=\(\dfrac{5}{6}\)
d) \(\dfrac{3}{4}\)x-\(\dfrac{2}{5}\)x=\(\dfrac{3}{7}\).\(\dfrac{1}{6}\)+\(\dfrac{5}{7}\).\(\dfrac{1}{6}\)
*Lưu ý: Trình bày chi tiết kết quả.
a)\(x=\left(\dfrac{3}{56}\cdot\dfrac{28}{9}\right):\dfrac{-3}{7}=\dfrac{1}{6}:\dfrac{-3}{7}=-\dfrac{7}{18}\)
b)\(x=\left(\dfrac{7}{15}\cdot\dfrac{5}{3}\right)+\dfrac{3}{16}=\dfrac{7}{9}+\dfrac{3}{16}=\dfrac{139}{144}\)
c)\(x=\left(\dfrac{5}{6}-\dfrac{2}{5}\right).5=\dfrac{13}{6}\)
d)\(=>x\left(\dfrac{3}{4}-\dfrac{2}{5}\right)=\dfrac{1}{6}\cdot\left(\dfrac{3}{7}+\dfrac{5}{7}\right)\)
\(x\cdot\dfrac{7}{20}=\dfrac{4}{21}=>x=\dfrac{4}{21}\cdot\dfrac{20}{7}=\dfrac{80}{147}\)