11. 
    - It has been decided by them that the company will go to the beach together at the weekend.
    - The decision for the company to go to the beach together at the weekend has been made by them.
12. 
    - Maradona is thought by people to be the best football player in the 20th century.
    - It is thought by people that Maradona is the best football player in the 20th century.
13. 
    - The job is found by them to be not suitable for a girl like her.
    - It is found by them that the job is not suitable for a girl like her.
14. 
    - It was explained by the teacher that this powerful engine pulled the train.
    - That this powerful engine pulled the train was explained by the teacher.
15. 
    - I was told by him that his football team had played well last season.
    - That his football team had played well last season was told to me by him.

11.They have decided that the company will go to the beach together at the weekend.

=> It has been decided that the company will go to the beach together at the weekend. 

=> The company has been decided to go to the beach together at the weekend.
12.People think that Maradona is the best football player  in the 20^th century.

=> It is thought that Maradona is the best football player in the 20 th century

=> Maradona is thought to be the best football player in the 20 th century

13.They find that the job is not suitable for a girl like her.

=> It is found that the job is not suitable for a girl like her.

=> The job is found not to be suitable for a girl like her

14.The teacher explained that this powerful engine pulled the train.

=> It was explained that his powerful engine pulled the train

=> This powerful engine was explained to pull the train
15.He told me that his football team had played well last season.

=> It was told that his football team had played well last season.

=> His football team was told to have played well last season

a: Hiệu vận tốc hai xe là 60-37,5=22,5(km/h)

Hai xe gặp nhau sau 18:22,5=0,8(giờ)

b: Chỗ gặp nhau cách B: \(0,8\cdot37,5=30\left(km\right)\)

Số thứ nhất=0,6 số thứ ba

Hiệu số phần bằng nhau là 5-3=2(phần)

Số thứ nhất là 230:2*3=115*3=345

Số thứ ba là 345:0,6=575

Số thứ hai là 345:0,5=690 

8 giờ 45 phút*6-7 giờ 40 phút:2

=45 giờ 270 phút-6h100phút:2

=49 giờ 30 phút-3h50p

=48 giờ 90 phút-3 giờ 50 phút

=45 giờ 40 phút

8 giờ 45 phút x 6 - 7 giờ 40 phút : 2
=> 1890 phút - 230 phút = 1660 phút
Đổi: 1660 phút = 27 giờ 40 phút.

Câu 8: ông

Câu 9: ông

26 giờ 7 phút-9 giờ 54 phút

=25 giờ 67 phút-9 giờ 54 phút

=16 giờ 13 phút

9,7 giây*6

=58,2 giây

21 phút 25 giây:5

=20 phút 85 giây:5

=4 phút 17 giây

Tổng vân tốc hai xe là 55+45=100(km/h)

Hai xe gặp nhau sau 240:100=2,4(giờ)

Chỗ hai xe gặp nhau cách A: \(45\cdot2,4=108\left(km\right)\)

Độ dài cạnh hình lập phương là \(\sqrt{\dfrac{540}{6}}=\sqrt{90}=3\sqrt{10}\left(cm\right)\)

Thể tích hình lập phương là \(\left(3\sqrt{10}\right)^3=27\cdot10\sqrt{10}=270\sqrt{10}\left(cm^3\right)\)

thể tích của hình lập phương là =27 cm3

a: Chiều dài là 1,2:80%=1,5(m)

Chiều cao của bể là 4,32:2:(1,5+1,2)=0,8(m)

Thể tích của bể là \(1,2\cdot1,5\cdot0,8=1,44\left(m^3\right)\)

b: Mực nước trong bể hiện tại là \(0,8\cdot65\%=0,52\left(m\right)\)

Mực nước cách miệng bể khoảng:

0,8-0,52=0,28(m)=2,8(dm)

diện tích quét vôi là khoảng 145.9728 mét vuông.