Tài liệu ôn tập Kì thi Toán học quốc tế HKIMO 2020 dành cho Khối 2+3

 Arithmetic 
6. Find the value of 1 3 5 7 9 11 13 15 . 
7. Find the value of 3 3 6 2 9 1 18 2 . 
8. Find the value of 123 294 377+206 . 
9. What is the number that should be filled in the blank if the equation below is 
correct? 
10. Refer to the puzzle, find the value of B. 
 2 
KỲ THI OLYMPIC TOÁN HỌC QUỐC TẾ - HKIMO 2020 
Đơn vị đồng tổ chức tại Việt Nam: Trường Đại học Thủ Đô Hà Nội và FERMAT Education. 
Email: hkimo@daihocthudo.edu.vn hoặc hkimo.fe@gmail.com. 
 Geometry 
16. How many square(s) is / are there in the figure below? 
17. A prism has 16 faces, how many vertice(s) does this prism have? 
18. By observing the pattern, what is the missing figure? 
 4 
KỲ THI OLYMPIC TOÁN HỌC QUỐC TẾ - HKIMO 2020 
Đơn vị đồng tổ chức tại Việt Nam: Trường Đại học Thủ Đô Hà Nội và FERMAT Education. 
Email: hkimo@daihocthudo.edu.vn hoặc hkimo.fe@gmail.com. 
24. How many odd number(s) is / are there in the following numbers from the 4th 
to the 18th ? 
 1, 2, 3, 5, 8, 13, 
25. Alice has 5 $1 coins, 4 $2 coins and 5 $5 coin, how many value(s) of a product 
can she buy without any changes? 
 6 
KỲ THI OLYMPIC TOÁN HỌC QUỐC TẾ - HKIMO 2020 
Đơn vị đồng tổ chức tại Việt Nam: Trường Đại học Thủ Đô Hà Nội và FERMAT Education. 
Email: hkimo@daihocthudo.edu.vn hoặc hkimo.fe@gmail.com. 
 Arithmetic 
6. Find the value of 179 219 121 181 281 119 . 
7. Find the value of 17 118 31 17 17 51 . 
8. Find the value of 500  2 500  4 500 5 500 10 500 50 . 
9. Find the value of 5 15 25 35 45 55 . 
10. Find the value of 1017 8 129 8 . 
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KỲ THI OLYMPIC TOÁN HỌC QUỐC TẾ - HKIMO 2020 
Đơn vị đồng tổ chức tại Việt Nam: Trường Đại học Thủ Đô Hà Nội và FERMAT Education. 
Email: hkimo@daihocthudo.edu.vn hoặc hkimo.fe@gmail.com. 
17. A prism has 36 edges, how many face(s) does this prism have? 
18. A square whose sides are 10cm long is cut into 25 squares of side length 2cm. 
What is the difference in perimeters between 25 small squares and the larger 
square? 
19. At least how many square(s) can be seen if observing the figure below from the 
right? 
20. By observing the pattern, what is the missing figure? 
 Combinatorics 
21. After Alice takes 11 peanuts and 6 peanuts from Peter and Mary respectively, 
they will have equal number of peanuts. How many peanut(s) did Peter have more 
than Alice originally? 
 10 
KỲ THI OLYMPIC TOÁN HỌC QUỐC TẾ - HKIMO 2020 
Đơn vị đồng tổ chức tại Việt Nam: Trường Đại học Thủ Đô Hà Nội và FERMAT Education. 
Email: hkimo@daihocthudo.edu.vn hoặc hkimo.fe@gmail.com. 
ĐỀ 3: 
 Logical Thinking 
1. If the day after tomorrow is Wednesday, which day of the week the day before 
yesterday is? 
2. 16 children form a column. Amy is the 7th position counting from the front. 
What is her position counting form behind? 
3. According to the pattern shown below, what is the number in the blank? 
 3 、 6 、 10 、 15 、 21 、 28 、 __ 、 . 
4. John goes home by taxi and he needs to pay $90. How much does he has to pay 
if he goes home by taxi with his father, mother and sister? 
5. According to the pattern shown below, how many  is / are there in the 12th 
group? 
 12 
KỲ THI OLYMPIC TOÁN HỌC QUỐC TẾ - HKIMO 2020 
Đơn vị đồng tổ chức tại Việt Nam: Trường Đại học Thủ Đô Hà Nội và FERMAT Education. 
Email: hkimo@daihocthudo.edu.vn hoặc hkimo.fe@gmail.com. 
 143、 139、 135、 131、 127、  
14. How many 3-digit number(s) having the units digit 1 is / are there? 
15. Fill the lines with ‘ + ‘ and ‘ x ‘ to make the equation below correct. 
 Geometry 
16. How many square(s) is / are there in the figure below? 
17. A prism has 9 faces, how many vertice(s) does this prism have? 
18. According to the pattern shown below, what is the figure in the space 
provided? 
19. At least how many square(s) can be seen if viewing the figure below from top? 
 14 
KỲ THI OLYMPIC TOÁN HỌC QUỐC TẾ - HKIMO 2020 
Đơn vị đồng tổ chức tại Việt Nam: Trường Đại học Thủ Đô Hà Nội và FERMAT Education. 
Email: hkimo@daihocthudo.edu.vn hoặc hkimo.fe@gmail.com. 
ĐỀ 4: 
 Logical Thinking 
1. What is the value of the number to represent “?” in the following table? 
2. According to the pattern shown below, how many triangle(s) is / are there from 
the 1th to the 99th symbol counting from the left? 
3. The age of Samuel 9 years ago is equal to the age of Joseph 2 years later. How 
much Samuel is older than Joseph when Joseph is 25 years old? 
 16 
KỲ THI OLYMPIC TOÁN HỌC QUỐC TẾ - HKIMO 2020 
Đơn vị đồng tổ chức tại Việt Nam: Trường Đại học Thủ Đô Hà Nội và FERMAT Education. 
Email: hkimo@daihocthudo.edu.vn hoặc hkimo.fe@gmail.com. 
12. The sum of A and B is 2018. The difference between A and B is 902. Given A is 
larger than B, find the value of A. 
13. The numbers below follow the arithmetic sequence, what is the sum of the 9th 
term and the 14th term? 
 12、 15、 18、 21、 24、  
14. A three digit number has remainder 5 when divided by 9. What is such number 
that is closest to 400? 
15. The sum of 3 consecutive odd numbers is 69. Find the smallest of the odd 
numbers. 
 Geometry 
16. How many square(s) is / are there in the figure below? 
 18 
KỲ THI OLYMPIC TOÁN HỌC QUỐC TẾ - HKIMO 2020 
Đơn vị đồng tổ chức tại Việt Nam: Trường Đại học Thủ Đô Hà Nội và FERMAT Education. 
Email: hkimo@daihocthudo.edu.vn hoặc hkimo.fe@gmail.com. 
 Combinatorics 
21. After Amy gives 10 apples to Andy and 7 apples to Johnny, they will have 
equal number of apples. How many apple(s) did Johnny have less than Amy 
originally? 
22. Choose 3 digits from 1, 3, 4, 5, 9 to form 3-digit numbers. How many 
number(s) that can be divisible by 5 is / are there? (repetitions of digits are 
allowed) 
23. Numbers are drawn from the 27 integers 1 to 27. At least how many number(s) 
is / are drawn at random to ensure that there are two numbers whose difference is 
divisible by 4? 
24. At least how many of 37 children that was/were born in the same month? 
25. If Andy goes from point A to point B, each step can only move up or move 
right. How many way(s) is / are there? 
 20 
KỲ THI OLYMPIC TOÁN HỌC QUỐC TẾ - HKIMO 2020 
Đơn vị đồng tổ chức tại Việt Nam: Trường Đại học Thủ Đô Hà Nội và FERMAT Education. 
Email: hkimo@daihocthudo.edu.vn hoặc hkimo.fe@gmail.com. 
6. Find the value of 3 + 7 + 15 + 30 + 25 + 18 + 4 + 2 + 6. 
7. Find the value of 120 ÷2 + 120 ÷5 -120÷10. 
8. Find the value of 23-8 + 15-4 + 10 -5. 
9. What is the number that should be filled in the blank if the equation below is 
correct? 
 ___________ ×35 = 280 
10. If A and B are different 1-digit numbers, how many the value of A if the 
equation is correct? 
 AB – B = A0 
 Number Theory 
11. Anna has 66 apples and John has 24 apples. How many apples does Anna have 
to give John to make them have the same number of apples? 
12. 5 students have 65 balloons in total. Three children have even number of 
ballons and two childrens got odd number of ballons. Determine the number of 
balloons of the remaning child? 
13. The number below follow the arithmetic sequence, what is the 10th number? 
 120, 126, 132, 138, 144 
14. How many 3 – digit number(s) having the units digit 2 is/ are there? 
15. Fill the lines with “+” and “×” to make the equation below correct: 
 5____6_____7_____8______9 = 95 
 Geometry 
16. How many squares is/ are there in the figure below? 
 22 
KỲ THI OLYMPIC TOÁN HỌC QUỐC TẾ - HKIMO 2020 
Đơn vị đồng tổ chức tại Việt Nam: Trường Đại học Thủ Đô Hà Nội và FERMAT Education. 
Email: hkimo@daihocthudo.edu.vn hoặc hkimo.fe@gmail.com.