There ảre a lot of fun at the party last night.

🍀🍀🍀

Đơn vị của 2 là gì vậy ạ

Vậy \(n\in\left\{5;3;6;2;8;0;12;-4;20;-12\right\}\)

\(e,-\dfrac{1}{8}.\dfrac{5}{6}-\dfrac{1}{8}.\dfrac{1}{6}+\dfrac{\left(-2020\right)^0}{8}\)

=\(-\dfrac{1}{8}\left(\dfrac{5}{6}+\dfrac{1}{6}\right)+\dfrac{1}{8}\)

\(=-\dfrac{1}{8}+\dfrac{1}{8}=0\)

\(a,1\dfrac{1}{3}-\dfrac{3}{4}.\left(-\dfrac{8}{5}\right)+\left(-\dfrac{1}{5}\right)\)

\(=\dfrac{4}{3}-\left(-\dfrac{6}{5}\right)-\dfrac{1}{5}\)

\(=\dfrac{4}{3}+\dfrac{6}{5}-\dfrac{1}{5}=\dfrac{4}{3}+\left(\dfrac{6}{5}-\dfrac{1}{5}\right)\)

\(=\dfrac{4}{3}+1=\dfrac{7}{3}\)

\(b,\dfrac{5}{9}:2\dfrac{2}{5}-4\dfrac{5}{9}:2\dfrac{2}{5}=\dfrac{5}{9}:\dfrac{12}{5}-\dfrac{41}{9}:\dfrac{12}{5}\)

\(=\dfrac{5}{9}.\dfrac{5}{12}-\dfrac{41}{9}.\dfrac{5}{12}=\dfrac{5}{12}\left(\dfrac{5}{9}-\dfrac{41}{9}\right)\)\(=\dfrac{5}{9}.\left(-4\right)=-\dfrac{20}{9}\)

\(c,\left(-\dfrac{3}{4}+\dfrac{2}{3}\right):\dfrac{5}{11}+\left(-\dfrac{1}{4}+\dfrac{1}{3}\right):\dfrac{5}{11}\)

=\(\left(-\dfrac{3}{4}+\dfrac{2}{3}\right).\dfrac{11}{5}+\left(-\dfrac{1}{4}+\dfrac{1}{3}\right).\dfrac{11}{5}\)

=\(\dfrac{11}{5}\left(-\dfrac{3}{4}+\dfrac{2}{3}-\dfrac{1}{4}+\dfrac{1}{3}\right)\)

\(=\dfrac{11}{5}\left(-1+1\right)=\dfrac{11}{5}.0=0\)

d) \(\dfrac{1}{7}.\dfrac{3}{8}+\dfrac{1}{7}.\dfrac{5}{8}+\dfrac{\left(-1\right)^{2019}}{7}\)

=\(\dfrac{1}{7}\left(\dfrac{3}{8}+\dfrac{5}{8}\right)+\dfrac{-1}{7}=\dfrac{1}{7}.1-\dfrac{1}{7}\\\)

=1/7-1/7=0

Số táo của Lê là 51x2=102

Tổng số táo của hai bạn là 51+102=153

Câu 1

a(x)b+b(x)a=38

<=>a x b + a - b + b x a + b - a=38

<=>a x b + b x a = 38

<=>a ( b+b)=38

<=>a x 2 x b=38

<=>a x b =19

\(\Rightarrow\)a=1,b=19 hoặc a=19,b=1

\(\left(\dfrac{4}{5}-\dfrac{13}{20}\right):\dfrac{3}{5}=\left(\dfrac{16}{20}-\dfrac{13}{20}\right):\dfrac{3}{5}\)

\(=\dfrac{3}{20}\times\dfrac{5}{3}=\dfrac{5}{20}=\dfrac{1}{4}\)

 \(\left(\dfrac{32}{60}+\dfrac{2}{5}\right):3=\left(\dfrac{8}{15}+\dfrac{6}{15}\right):3\)

\(=\dfrac{14}{15}:3=\dfrac{14}{45}\)

Phía sau 3/5 là nhân đúng k ạ. Để mình làm