a) \(\frac{15}{16}\cdot\frac{4}{3}-\frac{1}{2}:\frac{5}{4}+3\)

\(=\frac{5}{4}-\frac{2}{5}+3\)

\(=\frac{25}{20}-\frac{8}{20}+\frac{60}{20}\)

\(=\frac{77}{20}=3\frac{17}{20}\)

b) \(\left(\frac{2}{3}-\frac{3}{8}\right):\left(\frac{3}{5}+\frac{1}{4}\right)\)

\(=\frac{7}{24}:\frac{17}{20}\)

\(=\frac{35}{102}\)

c) \(\frac{15}{8}\cdot\left(\frac{1}{3}+\frac{1}{8}\right)-\frac{3}{8}:\frac{3}{4}\)

\(=\frac{15}{8}\cdot\frac{11}{24}-\frac{1}{2}\)

\(=\frac{55}{64}-\frac{1}{2}\)

\(=\frac{23}{64}\)

d) \(\frac{20}{21}:\left(\frac{4}{5}-\frac{1}{10}\right)+\frac{13}{15}:\frac{5}{26}\)

\(=\frac{20}{21}:\frac{7}{10}+\frac{52}{15}\)

\(=\frac{200}{147}+\frac{52}{15}\)

\(=4\frac{608}{735}\)

a) Theo đề bài ra ta có:    \(x-2y=10\)

\(3x=5y\Rightarrow\frac{x}{5}=\frac{y}{3}\Rightarrow\frac{x}{5}=\frac{2y}{6}\)

Áp dụng tính chất của dãy tỉ số bằng nhau ta có:

\(\frac{x}{5}=\frac{2y}{6}=\frac{x-2y}{5-6}=\frac{10}{-1}=-10\)

\(\Rightarrow\begin{cases}\frac{x}{5}=-10\Rightarrow x=\left(-10\right)\cdot5=-50\\\frac{y}{3}=-10\Rightarrow y=\left(-10\right)\cdot3=-30\end{cases}\)

Công thức tính diện tích hình thang là:

\(\frac{\left(a+b\right)\cdot h}{2}\)

1. He does his homework at the moment.

            A      B                      C           D

2. The station is at the left at the end of the street.

                        A  B                          C                D

3. She will come home at a quarter pass five.

             A      B                C                   D

4. The students have four fifteen-minutes breaks each day.

                            A                       B                  C                D

5. He is learning cooking at the moment.

          A                    B         C          D

6. She is liking to play basketball because she thinks it is interesting.

                 A            B                             C                            D

7. The biggest desk is at the middle of the room.

                 A                B  C                   D

8. On History, we study the past and how the world changes.

     A                         B                     C                                D

9. The students follow she to the video room.

                  A                  B    C          D

10. In his free time, he learns cooking!

       A                B     C                  D

80 %

125 %

Cap        paddy         woman         crab

@Đỗ Nguyễn Như Bình \(\frac{2}{3^2}\) hay là \(\frac{2^2}{3}\) hay là \(\left(\frac{2}{3}\right)^2\) vậy em???????????

1.The waiter brings me this dish

I am brought this dish by the water.

2. Our friends send the postcards to us

The postcards are sent to us by our friends.

3.They told me that you were the best architect in this city

I was told that you were the best architect in this city.

4. She reported that the flowers were killed by frost.

The flowers were reported to be killed by frost.

5.That officer announced that the meeting was delayed until next week.

It was announced that the meeting was delayed until next week.