25 x 9 x 4 - 50 x 2 x 6 + 100

= 100 x 9 - 100 x 6 + 100

= 100 x ( 9 - 6 + 1 )

= 100 x 4 = 400 

25 x 9 x 4 - 50 x 2 x 6 + 100

=  ( 25  x 4 ) x 9 - ( 50 x 2 ) x 6 + 100

4*X +50=74

4*X=74-50=24

4*X=24/4=6

KO CẦN ĐỌC TIẾP NX

đag thi à?

\(a,\dfrac{6}{11}+6+\dfrac{5}{7}=\dfrac{42+462+55}{77}=\dfrac{559}{77}\)

\(b,\dfrac{9}{8}\times\dfrac{3}{12}:\dfrac{5}{9}=\dfrac{9}{8}\times\dfrac{3}{12}\times\dfrac{9}{5}=\dfrac{243}{480}=\dfrac{81}{160}\)

\(c,\dfrac{8}{7}:4+2=\dfrac{8}{7}\times\dfrac{1}{4}+2=\dfrac{8}{28}+2=\dfrac{2}{7}+2=\dfrac{16}{7}\)

\(d,\dfrac{3}{5}+4:\dfrac{6}{4}=\dfrac{3}{5}+4\times\dfrac{4}{6}=\dfrac{3}{5}+\dfrac{8}{3}=\dfrac{49}{15}\)

ô hoooho bắt lỗi dc câu d nhee, sai đề ròi :)

431/225

9/5 x 5/7=63/25

63/25 x 7/9=431/225

chúc học tốt

( 48 x 5 + 48 x 7 - 48 x 12 )

=48 x ( 5 + 7 - 12 )

=48 x 0

= 0

\(\Rightarrow\)( 48 x 5 + 48 x 7 - 48 x 12 ) : ( 1 + 3 + 5 + 7 +.....+ 91 ) = 0

Hk tốt

      \(\left(48\text{ x }5+48\text{ x }7-48\text{ x }12\right)\text{ : }\left(1+3+5+7+...+91\right)\)

\(=\left(48\text{ x }5+48\text{ x }7-48\text{ x }12\right)\text{ : }A\)

\(=48\text{ x }\left(5+7-12\right)\text{ : }A\)

\(=48\text{ x }\left(12-12\right)\text{ : }A\)

\(=48\text{ x }0\text{ : }A\)

\(=0\text{ : }A\)

\(=0\)

x x\(\frac{5}{8}\)= 15 -\(\frac{1}{2}\)

x x\(\frac{5}{8}\)=\(\frac{29}{2}\)

          x =\(\frac{29}{2}\):\(\frac{5}{8}\)

          x =\(\frac{116}{5}\)

Chúc bạn học tốt.

😁😁😁

\(x\times\frac{5}{8}=15-\frac{1}{2}\)

\(x\times\frac{5}{8}=14\)

\(x=14:\frac{5}{8}\)

\(x=\frac{112}{5}\)

= X*(2/3 + 1/5) = 26/15

=X*13/15 = 26/15

X=26/15 : 13/15

X=2

X x (2/3+1/5)=26/15

X x 13/15=26/15

X=26/15 : 13/15

X=2

\(\left(218.99+218\right)-\left(215.101-215\right)\)

\(=\left[218\left(99+1\right)\right]-\left[215\left(101-1\right)\right]\)

\(=218.100-215.100\)

\(=\left(218-215\right).100\)

\(=3.100\)

\(=300\)

học tốt

Cảm ơn bạn nha bạn Thanh Ngân !