Một sân trường hình chữ nhật có chiều dài 180m, chiều rộng bằng $\frac{4}{5}$ chiều dài. Tính chiều rộng của sân trường ?

Trả lời: Chiều rộng của sân trường ……. m

Bố 49 tuổi, tuổi con  bằng $\frac{2}{7}$ tuổi bố. Hỏi con bao nhiêu tuổi?

Trả lời: Con …… tuổi

Tìm $\frac{3}{4}$ của 64kg ?

Trả lời: Kết quả là: …….kg

Tìm $\frac{2}{3}$ của 24m ?

Trả lời: Kết quả là:……..m 

Calculate:

$1-\left( 1-\frac{1}{2} \right)\times \left( 1-\frac{1}{3} \right)\times \left( 1-\frac{1}{4} \right)\times ...\times \left( 1-\frac{1}{50} \right)$

( Write the result as a/b )

A rectangle and a square are given. One side of the square is equal to the width of rectangle. The perimeter of the rectangle is bigger than the perimeter of the square by 6cm. The area of the rectangle is bigger than the area of the square by 24cm2. Find the area of the rectangle. 

A square is given. Connect the midpoint of two consecutive side together of that square we have a second square.Connect the midpoint of two consecutive side together  of the second square  we get the third square. Connect the two diagonals of the given square. Find the total area of all the triangles in the figure. Knowing that the area of the given square is 156 cm² ?

Calculate:
$\frac{6}{\text{1x}3\text{x7}}+\frac{6}{3\text{x7x9}}+\frac{6}{\text{7x9x13}}+\frac{6}{9\text{x13x}15}+\frac{6}{\text{13x}15\text{x}19}$
( Write the result as a/b )

Triangle ABC is given. Point D and E lie on side AB so that AD = ED = DB. Point H and K lie on the side AC so that AH = HK = KC. Point M and N lie on side BV so that BM = MN = NC. Knowing that the area of triangle ABC is 360cm2. Find the area of the figure DEMNKH?

 On a map with scale of 1 : 6 000 000, the distance between Hue and Vungtau is 112mm. Find this distance in real life. ( kilometer ) 

The perimeter of a rectangle school garden is 180m. The width is $\frac{2}{3}$ the length. $\frac{1}{4}$ of the school garden is used to plant flower. What is the area for planted flower ?

Hung worked 4 days. Dung worked 5 days. Nam worked 7 days. They received the total money is 2240000 dong. How much money did each person receive ? ( Each person received the same amount of money for one day. )

The daily attendance of a school for 5 school days in a week was 729; 730; 727; 725 and 724

If the number of pupils of the school is 735. Find the average number of daily absence ?

The average of teacher and 35 students is 11 years old. Knowning that the age of teacher is 36 years old more than the average age of 35 students.Find the average age of 35 students ?

How many suitable numbers are there ?

$\overline{24*6*}$   is divisible by 2; 3 and 5 ?