for one rectangle is 150 cm in circumference, divided along the width to be in shape and a smaller rectangular square. the area of the original rectangle. aware of the size measurements are natural numbers
1>My class of 32 students are going to a Fun Fair for children and need to buy entrance tickets for each student. The price of an entrance ticket is 5,000 dong. The good news is that when we buy 5 tickets, the Fun Fair gives us 1 extra ticket for free. How much does my class have to pay to buy enough tickets for the whole class?
2>Minh’s family needs to tile the floor of a rectangular room, 5 m in length and 3.8 m in width, with square tiles. The length of the side of each tile is 0.5 m. Each of the tiles close to the wall, if not a whole one, is cut from a whole tile. The total number of tiles needed to tile the room is ?
3>A student cycles from home to school in a distance of 1,200 m with speed of 2.5 m/s. There are 4 crossroads on the way; the time to stop for red lights at each crossroad is 30 s the longest. The longest time it takes the student to reach school is?
A square of side 8cm has the same perimeter as a rectangle. If the ratio of the width of the rectangle to its length is 1:3 then its area is ....?
There is a shaded square inside a rectangle as shown. From A to B is 6 cm and from C to D is 8 cm. What is the perimeter of the large rectangle?
Question 10:
A square of side 8cm has the same perimeter as a rectangle. If the ratio of the width of the rectangle to its length is 1:3 then its area is
Combinatorics
21. 15 students join a competition. Only top 5 students can be promoted to next round. How many different way(s) of promotion advance is / are there?
Different way: Cách khác nhau.
22. It is known that there are 8 classes of grade 5 in a primary school. At least how many students are there in grade 5 to ensure there exist 41 students in the same class?
At least: Ít nhất; Ensure: Chắc chắn; Exist: Tồn tại.
23. Choose 3 digits from 1, 2, 3, 4, 6, 8 and 0 to form 3-digit numbers. How many even number(s) greater than 300 is / are there? (The repetition of digits is not allowed)
Digit: Chữ số; 3-digit number: Số có 3 chữ số; Even number: Số chẵn; Greater than: Lớn hơn; Repetition of digits is not allowed: Các chữ số không được lặp lại.
24. A flight of stairs has 10 steps. Peter can go up for 1 step, 2 steps or 3 steps each time. How many way(s) is / are there for Peter to go up the stairs?
Step: Bước; Way: Cách.
25. Numbers are drawn from 80 integers 20 to 99. At least how many number(s) is / are drawn at random to ensure that there are two numbers whose sum is 85?
Integer: Số nguyên; At least: Ít nhất; Random: Ngẫu nhiên; Ensure: Chắc chắn; Sum: Tổng.
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Combinatorics
21. 15 students join a competition. Only top 5 students can be promoted to next round. How many different way(s) of promotion advance is / are there?
Different way: Cách khác nhau.
22. It is known that there are 8 classes of grade 5 in a primary school. At least how many students are there in grade 5 to ensure there exist 41 students in the same class?
At least: Ít nhất; Ensure: Chắc chắn; Exist: Tồn tại.
23. Choose 3 digits from 1, 2, 3, 4, 6, 8 and 0 to form 3-digit numbers. How many even number(s) greater than 300 is / are there? (The repetition of digits is not allowed)
Digit: Chữ số; 3-digit number: Số có 3 chữ số; Even number: Số chẵn; Greater than: Lớn hơn; Repetition of digits is not allowed: Các chữ số không được lặp lại.
24. A flight of stairs has 10 steps. Peter can go up for 1 step, 2 steps or 3 steps each time. How many way(s) is / are there for Peter to go up the stairs?
Step: Bước; Way: Cách.
25. Numbers are drawn from 80 integers 20 to 99. At least how many number(s) is / are drawn at random to ensure that there are two numbers whose sum is 85?
Integer: Số nguyên; At least: Ít nhất; Random: Ngẫu nhiên; Ensure: Chắc chắn; Sum: Tổng.
~ End of Paper ~
1/- Compare : A = (1+3+5+...+139)/70 and B = (2+4+6+...+138)/69
Answer : A......... B
2/- In the follwing figure , ABED and BCFE are square . If the perimeter of the rectangle ACFD is 54cm . Then its area is :
3/- Calculate : 4/16 + 6/15 + 8/14 + 3/7 + 3/5 + 3/4 = ?
( Write your answer in the simplest form . )