1. Mai usually listens to K-pop music in her free time.

2. When I was a child, I enjoyed playing computer games.

3. My father spends most of his spare time looking after the garden.

4. Is watching TV the most popular leisure activity in Britain?

5. Many teenagers are addicted to the Internet and computer games.

6. She got hooked on the medical drama after watching the first episode.

7. Most of my friends prefer playing sports to surfing the net.

8. In today's world, teenagers rely on technology more than in the past.

Câu 3: 

a: Áp dụng tính chất của dãy tỉ số bằng nhau, ta được:

\(\dfrac{x}{3}=\dfrac{y}{2}=\dfrac{x+y}{3+2}=\dfrac{90}{5}=18\)

Do đó: x=54; y=36

Câu 1: C

Câu 2: A
Cau 3: C

Câu 8: C

Câu 7: A

a, \(\frac{12\times3\times4}{24\times25\times26}\)=\(\frac{12\times3\times2\times2}{12\times2\times25\times13\times2}\)=\(\frac{1\times3\times1\times1}{1\times1\times25\times13\times1}\)=\(\frac{3}{25\times13}\)=\(\frac{3}{325}\)

b, \(\frac{5}{8}\)\(\times\)\(\frac{3}{7}\)\(+\)\(\frac{5}{8}\)\(\times\)\(\frac{4}{7}\)= \(\frac{5}{8}\)\(\times\)\((\)\(\frac{3}{7}\)\(+\)\(\frac{4}{7}\)\()\)

                                                                       = \(\frac{5}{8}\)\(\times\)\(1\)=\(\frac{5}{8}\)

thanks

a) \(\frac{12.3.4}{24.25.26}=\frac{3.2.2.3.4}{2.3.4.25.2.13}=\frac{3}{13.25}\)(Hình như đề có gì sai sai)

b) \(\frac{5}{8}.\frac{3}{7}+\frac{5}{8}.\frac{4}{7}=\frac{5}{8}\left(\frac{3}{7}+\frac{4}{7}\right)=\frac{5}{8}.1=\frac{5}{8}\)

giúp gì bạn

\(\left(3\sqrt{7}\right)^2=63>28=\left(\sqrt{28}\right)^2\) hoặc \(3\sqrt{7}>2\sqrt{7}=\sqrt{28}\)

C1: $\sqrt{28}=\sqrt{4.7}=2\sqrt 7$

Ta có: $3>2$

$\Leftrightarrow 3\sqrt 7>3\sqrt 7$ hay $3\sqrt 7>\sqrt{28}$

C2: $3\sqrt{7}=\sqrt{63}$

Ta có: $63>28$

$\Leftrightarrow\sqrt{63}>\sqrt{28}$ hay $3\sqrt 7>\sqrt{28}$