Skip to content / Đến nội dung
ThichHocToan.com

BBB 2022 - Primary 6 - Preliminary Round

Question 1

Find the value of $2^0-2^1+2^2-2^3$.
  1. −5
  2. −4
  3. −6
  4. −3

Question 2

A 4-digit natural number is divided by 12 and 16 to get the same remainder of 2. What is the minimum value of this number?
  1. 1006
  2. 1154
  3. 1150
  4. 1010

Question 3

It takes Mickey 4 hours to paint a wall. It takes Minnie 6 hours to paint that wall. How long does it take both people to paint that wall?
  1. 10 hours
  2. 25 minutes
  3. 144 minutes
  4. 160 minutes

Question 4

If $2\otimes3=3\times5$ and $3\otimes8=8\times11\times14$, find the value of $(3\otimes6):(3\otimes3)$.
  1. 2
  2. 3
  3. 4
  4. 6

Question 5

Refer to the figure below, how many rectangle(s) is / are there?

Question illustration
  1. 32
  2. 36
  3. 34
  4. 30

Question 6

Find the value of $\frac3{4\times6}+\frac3{6\times8}+\frac3{8\times10}+\cdots+\frac3{44\times46}+\frac3{46\times48}$.
  1. $\frac{11}{72}$
  2. $\frac{11}{32}$
  3. $\frac{11}{48}$
  4. $\frac{11}{64}$

Question 7

The sum of 2 prime numbers is 24. Find the minimum value of the product of these 2 prime numbers.
  1. 63
  2. 95
  3. 143
  4. 119

Question 8

Find the value of $1992\times1995-1990\times1997$.
  1. 8
  2. 6
  3. 4
  4. 10

Question 9

Find the sum of all interior angles in the pentagon below.

Question illustration
  1. $360^\circ$
  2. $480^\circ$
  3. $540^\circ$
  4. $450^\circ$

Question 10

Now the total weight of a full water bottle is 544g. After throwing half water out, the remaining weight will be 324g. What is the net weight of the water bottle in g?
  1. 112 g
  2. 222 g
  3. 104 g
  4. 206 g

Question 11

How many positive factors of 3600 are there?
  1. 16
  2. 45
  3. 40
  4. 36

Question 12

Given 2 identical squares and 4 identical rectangles to form a big rectangle with perimeter 216cm as below. Find the area of one square in cm².

Question illustration
  1. 324 cm²
  2. 256 cm²
  3. 144 cm²
  4. 576 cm²

Question 13

At 6 o’clock, a truck travels from A to B with the speed of 40km/h. After 1 hour and a half, another car travels from A with the speed of 60km/h to catch the truck. When does 2 vehicles meet?
  1. 09:00
  2. 10:00
  3. 10:30
  4. 09:30

Question 14

Today is 13th October 2022, Thursday. Which year will satisfy that 13th October will be Wednesday for the earliest case?
  1. 2027
  2. 2028
  3. 2029
  4. 2026

Question 15

Now there are 300 people in a book club. 20% of the members are over 50 years old. 40% of the members are from 20 – 50 years old. How many people under 20 years old should join to make them 60% of the club?
  1. 100
  2. 150
  3. 120
  4. 180

Question 16

Given a square. Wendy draws 2 quarters whose centers are vertices of the squares as below. If the perimeter of the shaded region is $4\pi$, find its area.

Question illustration
  1. $8\pi-16$
  2. $32\pi-16$
  3. $16\pi-16$
  4. $16\pi-32$

Question 17

Use 0, 2, 5, 8, 6 without repetition. How many even 3-digit numbers can be formed?
  1. 36
  2. 48
  3. 39
  4. 24

Question 18

There is a cuboid. When the length increases 4cm, the volume will be increased by 144cm³. When the width decreases 3cm, the volume will be decreased by 144cm³. When the height increases 2cm, the volume will be increased by 96cm³. What is the volume of the cuboid in cm³?
  1. 512
  2. 216
  3. 384
  4. 288

Question 19

How many 3-digit numbers divisible by 4 but not divisible by 6 are there?
  1. 150
  2. 188
  3. 75
  4. 167

Question 20

Numbers are drawn from 60 integers 11 to 70. At least how many numbers are drawn at random to ensure that there are two numbers whose difference is 5?
  1. 16
  2. 26
  3. 31
  4. 21