3/11x7/19+3/11x17/19-3/11x24/19

=3/11x(7/19+17/19-24/19)

=3/11x0

=0

Bài làm

\(\frac{3}{11}\times\frac{7}{19}+\frac{3}{11}\times\frac{17}{19}-\frac{3}{11}\times\frac{24}{19}\)

\(=\frac{3}{11}\times\left(\frac{7}{19}+\frac{17}{19}-\frac{24}{19}\right)\)

\(=\frac{3}{11}\times\frac{0}{19}\)

\(=\frac{3}{11}\times0\)

\(=0\)

# Học tốt #

\(\frac{3}{11}\)x \(\frac{7}{19}\)+ \(\frac{3}{11}\)x \(\frac{17}{19}\)- \(\frac{3}{11}\)x \(\frac{24}{19}\)

= \(\frac{3}{11}\)x (\(\frac{7}{19}\)+ \(\frac{17}{19}\)- \(\frac{24}{19}\))

= \(\frac{3}{11}\)x 0

= 0

giúp mình bài này với

bạn nam đọc 1 quyển sách trong 3 ngày . ngày 1 đọc 1 phần 3 số trang . ngày thứ 2 đọc 2 phần 5 số trang còn lại .ngày 3 đọc 36 trang còn lại. hỏi quyển sách có bao nhiêu trang

mình giúp bạn thì bạn giúp mình nhé

6A=5.7.6+7.9.6+9.11.6+11.13.6+13.15.6+...+99.101.6

6A=5.7.(9-3)+7.9.(11-5)+9.11.(13-7)+11.13.(15-9)+13.15.(17-11)+...+99.101.(103-97)

6A=-3.5.7+5.7.9-5.7.9+7.9.11-7.9.11+9.11.13-9.11.13+11.13.15-11.13.15+13.15.17-...-97.99.101+99.101.103

6A=99.101.103-3.5.7 => A=(99.101.103-3.5.7)/6

1) \(=\left(\frac{3}{5}+\frac{2}{5}\right).\frac{6}{11}\)

\(=1.\frac{6}{11}\)

\(=\frac{6}{11}\)

2)\(\frac{17}{25}.\left(\frac{11}{19}+\frac{6}{19}+\frac{2}{19}\right)\)

\(=\frac{17}{25}.1\)

\(=\frac{17}{25}\)

2.\(\frac{17}{25}.\frac{11}{19}+\frac{17}{25}.\frac{6}{19}+\frac{17}{25}.\frac{2}{19}=\frac{17}{25}\left(\frac{11}{19}+\frac{6}{19}+\frac{2}{19}\right)\\ =\frac{17}{25}.1\\ =\frac{17}{25}\)

Minh dang lam bai ban doi chut nhe, ti minh giai cho

dc chưa

dc chưa

A, 7x - x = 5^21 : 5^19 + 3 . 2^2 - 7^0

      6x     =    5^2 + 3 . 4 - 1

      6x     =    25 + 12 - 1

      6x     =    37 - 1

      6x     =      36

        x     =      6.

B, mình giải ra nhưng số to quá. Bạn thử kiểm tra lại đề xem.

C, 7x - 2x = 6^17 : 6^15 + 44 : 11

       5x      =    6^2 + 4

       5x      =    40

         x      =   8.

thank you Nguyen Thanh Van

 Tinh Tong

A=1+2+3+....+999

B=21+23+25+...+1001

C=23+24+...+127+128

D=15+17+19+21+...+151+153+155

\(a,\dfrac{7}{-25}+\dfrac{-18}{25}+\dfrac{4}{23}+\dfrac{5}{7}+\dfrac{19}{23}\)

\(=\left(\dfrac{-7}{25}+\dfrac{-18}{25}\right)+\left(\dfrac{4}{23}+\dfrac{19}{23}\right)+\dfrac{5}{7}\)

\(=\left(-1\right)+1+\dfrac{5}{7}\)

\(=0+\dfrac{5}{7}=\dfrac{5}{7}\)

b, \(\dfrac{7}{19}.\dfrac{8}{11}+\dfrac{7}{19}.\dfrac{3}{11}+\dfrac{12}{19}\)

\(=\dfrac{7}{19}\left(\dfrac{8}{11}+\dfrac{3}{11}\right)+\dfrac{12}{19}\)

\(=\dfrac{7}{19}.1+\dfrac{12}{19}\)

\(=\dfrac{7}{19}+\dfrac{12}{19}=1\)

a. \(\dfrac{7}{-25}+\dfrac{-18}{25}+\dfrac{4}{23}+\dfrac{5}{7}+\dfrac{19}{23}\)

\(=\left(\dfrac{-7}{25}+\dfrac{-18}{25}\right)+\left(\dfrac{4}{23}+\dfrac{19}{23}\right)+\dfrac{5}{7}\)

\(=-1+1+\dfrac{5}{7}\)

\(=\dfrac{5}{7}\)

b. \(\dfrac{7}{19}\cdot\dfrac{8}{11}+\dfrac{7}{19}\cdot\dfrac{3}{11}+\dfrac{12}{19}\)

\(=\dfrac{7}{19}\left(\dfrac{8}{11}+\dfrac{3}{11}\right)+\dfrac{12}{19}\)

\(=\dfrac{7}{19}\cdot1+\dfrac{12}{19}\)

\(=\dfrac{7}{19}+\dfrac{12}{19}\)

\(=1\)

a. \(\dfrac{7}{-25}+\dfrac{-18}{25}+\dfrac{4}{23}+\dfrac{5}{7}+\dfrac{19}{23}\)

= \(\left(\dfrac{7}{-25}+\dfrac{-18}{25}\right)+\left(\dfrac{4}{23}+\dfrac{19}{23}\right)+\dfrac{5}{7}\)

= \(\left(-1\right)+1+\dfrac{5}{7}\)

= \(0+\dfrac{5}{7}=\dfrac{5}{7}\)

b. \(\dfrac{7}{19}.\dfrac{8}{11}+\dfrac{7}{19}.\dfrac{3}{11}+\dfrac{12}{19}\)

= \(\dfrac{7}{19}.\left(\dfrac{8}{11}+\dfrac{3}{11}\right)+\dfrac{12}{19}\)

= \(\dfrac{7}{19}.1+\dfrac{12}{19}\)

= \(\dfrac{7}{19}+\dfrac{12}{19}=1\)

có đúng ko