100

100

100

\(\frac{\left(315+372\right).3+\left(372+315\right).7}{26.13+74.48}\)

\(=\frac{\left(315+372\right).\left(3+7\right)}{\left(26.13\right)+\left(74.48\right)}\)

\(=\frac{687.10}{39+3552}\)

\(=\frac{6870}{3890}=\frac{687}{389}\)

\(B=\frac{\left(315+372\right).3+\left(372+315\right).7}{26.13+74.14}=\frac{315.3+372.3+372.7+315.7}{26.13+74.14}=\frac{315.\left(7+3\right)+372.\left(7+3\right)}{26.13+74.14}=\frac{3150+3720}{26.13+74.14}\)

đến đấy bó tay

(-315) - (2019-315)= (-315) - 1704 = -2019

(- 35 ) - (2019 - 315 ) = ( -  35 ) - 1704 = 2019

tui chẳng hiểu gì nha

thanks all

\(A=2\frac{1}{315}\cdot\frac{1}{651}-\frac{1}{105}\cdot3\frac{650}{651}-\frac{4}{315\cdot651}+\frac{4}{105}\)

=\(\frac{1}{315}\cdot\frac{1}{651}+2\cdot\frac{1}{651}-\frac{1}{105}\cdot\left(4-\frac{1}{651}\right)-\frac{4}{315}\cdot\frac{1}{651}+\frac{4}{105}\)

=\(\frac{1}{315}\cdot\frac{1}{651}+2\cdot\frac{1}{651}-\frac{4}{105}+\frac{1}{105}\cdot\frac{1}{651}-\frac{4}{315}\cdot\frac{1}{651}+\frac{4}{105}\)

=\(\frac{1}{651}\cdot\left(\frac{1}{315}+\frac{1}{105}+2-\frac{4}{315}\right)\)+\(\frac{4}{105}-\frac{4}{105}\)

=\(\frac{2}{651}\)

Bạn sai dấu trừ ở trước số 4 phần 105 phải là cộng mình làm bài này rồi

giải cách này cũng được nè:
Đặt \(x\)=\(\frac{1}{315}\)  ; \(y\)=\(\frac{1}{651}\)  ; \(z\)=\(\frac{1}{105}\)
A=\(2\frac{1}{315}\cdot\frac{1}{651}-\frac{1}{105}\cdot3\frac{650}{651}-\frac{4}{315\cdot651}+\frac{4}{105}\)
 =\(\left(2+\frac{1}{315}\right)\cdot\frac{1}{651}-\frac{1}{105}\cdot\left(4-\frac{1}{651}\right)-4\cdot\frac{1}{315}\cdot\frac{1}{651}+4\cdot\frac{1}{105}\)
 =\(\left(2+x\right)y-z\left(4-y\right)-4xy+4z\)
 =\(2y+xy-4z+zy-4xy+4z\)
 =\(2y+zy-3xy\)
 =\(2\cdot\frac{1}{651}+\frac{1}{105}\cdot\frac{1}{651}-3\cdot\frac{1}{315}\cdot\frac{1}{651}\)
 =\(\frac{2}{651}+\left(\frac{1}{105}\cdot\frac{1}{651}-\frac{1}{105}\cdot\frac{1}{651}\right)\)
 =\(\frac{2}{651}+0=\frac{2}{651}\)

\(\frac{2}{651}\)nhé bạn

\(92\cdot4-27=\frac{y+350}{y}+315\Leftrightarrow\frac{y+350}{y}=26\Leftrightarrow y+350=26y\Leftrightarrow350=25y\Leftrightarrow y=14\)