\(A=20,09\times100+2009\times\frac{100}{25}+200,9:0,1+2,009:0,001\)

    \(=2009+2009\times4+2009+2009\)

      \(=2009\times\left(1+4+1+1\right)\)

      \(=2009\times7=14093\)

A=20,09x100+2009x100/25+200,9:0,1+2,009:0,001

A=2009+2009x4+200,9x10+2,009x1000

A=2009+2009x4+2009+2009

A=2009x(1+4+1+1)

A=2009x7

A=14,063

Chúc bn học tốt

Thanks 2 bẹn nhá!!!

a] 57 + 26 + 24 + 63

=( 57+63 )+ ( 26 + 24 )

=120 +50

=170

b) 24 + 25 + 26+27+28 + 29 + 30 + 31

=( 24+ 31) x ( 31-24 ) +1 : 2

=55 x 4

=220

c) 199 + 36 + 201 + 184 + 37

= ( 199 + 201 ) + ( 36 + 184 ) + 37

= 400 + 220 + 37

=657

d) 2 + 4 + 6 + 8 + 10 +.......+ 100

=( 100 + 2 ) x ( 100-2 ) : 2 + 1 : 2

= 102 x 25 

=2550

Tk cho mk nha tk ai tk mk kb cho 

a) = 57 + 63 + 26 + 24

    = 120 + 50

    = 170 ( có nhanh ko ta?! làm theo quán tính hoy)

b) = (31+24) \(\times\)8: 2

    = 220

c) = 199 + 201+ 36+ 184 + 37

    = 400+ 220 + 37

    = 657

d) SSH= ( 100-2) : 2 + 1= 47

     Tổng= (100+2) \(\times\)47: 2= 2397

 check bạn nha!!! ^^

a) 57 + 26 + 24 + 63 = ( 57 + 63 ) + ( 26 + 24 ) = 120 + 50 = 170

b) 24 + 25 + 26 + 27 + 28 + 29 + 30 + 31 = ( 24 + 26 ) + ( 25 + 30 ) + ( 27 + 28 ) + ( 29 + 31 ) = 50 + 55 + 55 + 60 = 105 + 115 = 220

c) 199 + 36 + 201 + 184 + 37 = ( 199 + 201 ) + ( 36 + 184 ) + 37 = 400 + 220 + 37 = 657

d) 2 + 4 + 6 + 8 + 10 +...+100 

Số số hạng dãy số này có là :

( 100 - 2 ) : 2 + 1 = 50 ( số hạng )

Tổng của dãy số này là :

( 2 + 100 ) x 50 : 2 = 2550 

Eat well, do morning exercises, never eat too much candy, never stay up too late, and get up early!!

You should eat enough groups of substances, get up early exercise, eat less fast food and play healthy sports...

Our bodies are built of and powered by solely what we eat and drink. Food is the source of all of the energy needed Why do humans have to eat? Is it just because we get hungry? That is not all. People get energy from food. We need energy all the time, when we run, jump, sing, and even when we sleep. We create all the energy we need by eating. The structures components that make up the human body, such as muscles, organs, and bones, are also composed of the nutrients contained in food, meaning that it is. This is why eating and taking in the nutrients that provide energy and become the components of our bodily structures is essential to for sustaining human life.

Fill in each of the blanks using the words given in the box.

and, some, have, who, types

Vitamins are very important for the body. There are more than thirtem (1)______types_____ of vitamins. They help the body take (2)______some_____ energy from foods, help the body grow, (3)___and____ muscles work correctly. Vitamin A is necessary for our eyes. People (4) ____who____ don't have enough vitamin A often (5) _____have_____ night blindness; that is, they can't see well when it is dark. Food such as liver, eggs, milk, and cheese have a lot of vitamin A.

vocabulary about the parts of the body; _eyes_

1. Some body clean the house every day

=> The house is cleaned everyday.

2.how do people learn language?

=> How is language learned?

3. John will collect me at the airport

=> I will be collected at the airport by John.

4.mr.Robinson teaches us how to speak english properly

=> We are taught how to speak English properly by Mr.Robinson.

5.your techer must sign this form

=> This form must be singed by your teacher.

6.people play football all over the world

=> Football is played all over the world.

7.our form teacher will hold a class discussion next monday

=> A class discussion will be held by our form teacher next monday.

8.will you invite her to your birthday party

=> Will she be invited to your birthday party?

9. We can't wear jeans at work

=> Jeans can't be worn at work.

giảm đường kính đi 20% thì bán kính cũng giảm đi 20%

bán kính của hình tròn mới là 100% – 20%= 80%

diện tích hình tròn có bán kính 80% là 80% * 80% = 64%

diên tích hình tròn cũ hơn hình tròn mới là 100% * 100% – 64%= 36%

36%=113,04cm² => diện tích hình tròn ban đầu là 113,04: 36 * 100 = 314cm²