Câu 1:
A is a set of multiples of 12 less than 12. How many elements does the set A have?
Answer: The set A has  element(s)

Câu 2:
Find the remainder when  is divided by 9.
Answer: The remainder is 

Câu 3:
Find the remainder of  when it is divided by 3.
Answer: The remainder is 

Câu 4:
A is the set of factor of 12 more than 6. How many elements does the set A have?
Answer: The set A has  element(s)

Câu 5:
Find the natural number  so that the product of  and 5 is a prime number.
Answer: 

Câu 6:
Given that . How many divisors does the number A have?
Answer: The number A has  divisors.

Câu 7:
Given that . How many divisors does the number A have?
Answer: The number A has  divisors.

Câu 8:
How many prime numbers less than 10 are there?
Answer: There are  numbers. 

Câu 9:
Find the greatest 2-digit number that has 12 divisors.
Answer: It is 

Câu 10:
Among all natural number pairs  satisfy , one pair has the greatest product. What is this product?
Answer: The greatest product is 

Write the words in number form which consist of: 7 hundred thousands, 6 thousands, 3 hundreds, 4 tens and 2 units.
Answer: 

Câu 2:
Fill in the sequence with the missing number in order to have 3 consecutive natural numbers.
897;  ; 899

Câu 3:
Fill in the sequence with the missing number in order to have 3 consecutive natural numbers.
; 87; 88

Câu 4:
How many single digit numbers are there?
Answer:  numbers.

Câu 5:
6 is just after of 5 and 5 is just before of 6. What is the product of just after and just before of 10?
Answer: 

Câu 6:
Jean has 3014 beads. She has 497 beads less than Gillian. How many beads do they have altogether?
Answer: They have  beads altogether.

Câu 7:
There are 56 apples in a basket.  of them are green and the rest are red. How many red apples are there?
Answer: There are  red apples.

Câu 8:
The perimeter of a square garden is 36m. What is its area?
Answer: Its area is  .

Câu 9:
248 boys and 418 girls were divided into groups of 9. How many groups were there altogether?
Answer:  groups.

Câu 10:
Mr Junior bought 1 magazine, 1 book and 1 pen. The pen costs 5 dollar, the book costs 31 dollar more than the pen. The magazine costs twice as much as the book. How much did he spend on the three things?
Answer: He spent  dollar.

Exer 1: There is a division with the quotient is 6 and the remainder is 3. The sum of dividend, divisor and remainder are 195. Find the dividend are divisor.

Exer 2: Prove that: Amoney three consecutive natural numbers, there is one only one the number which divisibles by 3.

Exer 3: Given natural number, n = \(\overline{1ab1}\). Let m be the natural number which is written the opposite respectively of n. Prove that the different of n and m divisibles by 90.

Question 1:
K is a prime number and a multiple of 43. What is K?
Answer: K = 

Question 2:
How many prime numbers are less than 10? 
Answer: There are  numbers.

Question 3:
The smallest factor of 82 is 

Question 4:
The smallest multiple of 47 is 

Question 5:
In the following figure, RQ = 12cm and PR = 17cm. PQ = cm
 

Question 6:
In the following figure, AN = 5cm and AB = 8cm. NB = cm
 

Question 7:
A prime number between 42 and 46 is 

Question 8:
Find the sum of all the factors of 19
Answer: 

Question 9:
The sum of two of following numbers is divisible by 4 and 6. 
What are the two numbers?

(Write numbers in order, beginning smaller and use “;”)
Answer: 

Question 10:
How many prime numbers have formed ?
Answer: There are  numbers