a; N = 15,32 + 27,4 - 4,25 x 2

    N = 42,72 - 8,5

   N = 34,22

b; M = (227,45 - 142,65) : 3,2 - 25

    M = 84,8 : 3,2 - 25

    M = 26,5 - 25

    M = 1,5

Diện tích sân chơi là:

\(\left(\right. 12 , 4 + 8 , 6 \left.\right) \times 8 , 5 : 2 = 89 , 25 \left(\right. m^{2} \left.\right)\)

Diện tích đài phun nước là:

\(2 \times 2 \times 3 , 14 = 12 , 56 \left(\right. m^{2} \left.\right)\)

Diện tích phần còn lại là:

89,25-12,56=76,69(m²)

AD=AM+MD=10+15=25(cm)

\(S_{A B C D} = A B \times A D\)

=>\(A B = \frac{1000}{25} = 40 \left(\right. c m \left.\right)\)

=>DC=40(cm)

\(S_{M D C} = \frac{1}{2} \times M D \times D C = \frac{1}{2} \times 15 \times 40 = 20 \times 15 = 300 \left(\right. c m^{2} \left.\right)\)

a) Diện tích hình thang đó là:

                 \(\frac{\left(\right. 9 + 11 , 5 \left.\right) \times 6 , 2}{2} = 63 , 55 \left(\right. c m^{2} \left.\right)\)

b) Bán kính hình tròn đó là:

                   \(31 , 4 : 3 , 14 : 2 = 5 \left(\right. c m \left.\right)\)

     Diện tích hình tròn đó là:

                    \(5 \times 5 \times 3 , 14 = 78 , 5 \left(\right. c m^{2} \left.\right)\)

                                Đáp số: a) \(63 , 55 c m^{2}\)

                                              b) \(78 , 5 c m^{2}\)

a: 15,6+32,88=48,48

b: 158,08-97,15=60,93

c: 15,45x1,6=24,72

d: 75:60=1,25

1. My name's Thao Nhi, I'm 10 years old.

2. My favourite color is Pastel blue, my favorite animal is penguin, my favourite food is vegetable and my favourite sport is badminton.

3. My brother is thin, short and he has a short hair. My teacher thin, tall. She has a found face and a big eyes.

4. I and my family is watching Tv in the weekend.

5. I want to be a artist beacause I can creative and draw according to my preferences.

Q1. Her nationality is Vietnamese.

Q2. It's 47 Queen Street.

Q3. He would like to be a firefighter in the future.

Q4. He likes cooking.

Q5. She likes to practise the piano in her free time.

I have a friend. She is very friendly and always helps her friends. She has shiny blonde hair and a round face. She is tall. I am very happy to be her friend.