IX
hai dấu của chữ X sẽ thành chữ V rồi sau đó V sẽ đổi chỗ cho I
IX
hai dấu của chữ X sẽ thành chữ V rồi sau đó V sẽ đổi chỗ cho I
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 ~
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 ~
There are 48 students in a class. The ratio of the number of the girl students to the number of boy students is 1: 3. How many girl students are there in the class?
Answer: There are...... girl students.
There are 48 students in a class. The ratio of the number of the girl students to the number of boy students is 1: 3. How many girl students are there in the class?
There are 35 men and some of women in a meeting room. The ratio of the number of women to the number of men is 7:5 . How many women are there in the meeting room ?
There are 48 students in a class. The ratio of the number of the girl students to the number of boy students is \(\frac{1}{3}\). How many girl students are there in the class?
Use all the digits below to form the decimal number that is smaller than 5:2,5,9,4,8.How many such numbers are there?
Use all the digits below to form the decimal number that is smaller than 5
2,5,9,4,8
How many such numbers are there?
Use all the digits below to form the decimal number that is smaller than 5.
2; 5; 9; 4; 8
How many such numbers are there?
Use all the digits below to form the decimal number that is smaller than 5.
2; 5; 9; 4; 8
How many such numbers are there?