Tài liệu bổ trợ thi Violympic Toán tiếng Anh lớp 5

Write the result by decimal number with comma between number part and fraction part Question 3:.. Write 2/100 as a decimal number with comma between number part and fraction part.[r]

PRACTICE MATERIALS

FOR MATH VIOLYMPIC

GRADE 5

2016

CONTENTS

CONTENTS 1

ROUND 1 2

ROUND 2 7

ROUND 3 13

ROUND 4 18

ROUND 5 23

ROUND 6 27

ROUND 7 30

ROUND 8 34

ROUND 9 38

ROUND 10 42

CÁC DẠNG BÀI CƠ BẢN 44

1 Chọn các ô trong bảng 44

2 Hình học 45

3 Phần trăm 46

4 Tổng – Hiệu – Tỉ số 47

5 Vận tốc 47

6 Toán tính tuổi 48

7 Các bài toán về số 49

8 Toán tỉ lệ 50

ROUND 1 Question 1:

Which fraction is greater than 1?

37 minutes 48 seconds + 29 minutes 36 seconds = minutes 24 seconds

The missing number is

Hung has eighteen pens more than Dung

Dung has one third as pen as Hung Dung has

Question 9:

This year, Mai's mother is four times as old as Mai Four years ago, Mai's mother was thirty years old more than Mai

This year, Mai is years old

The missing number is

A 6

Spending 80000 dong on buying 5kg apples

Spending dong on buying 7kg apples

The quotient of two numbers is 2 and their product is 100 Find the sum of the two numbers

Answer: The sum is…………

Answer: There are……….small tables, ………….large tables

Question 27:

If the area of the smallest square is 12 cm2 , what is the area of the entire figure?

Answer: The area of the entire figure is ………cm2

Find the sum of numbers that are greater than 50 in the following table

Answer: The sum is ………

3/5 of tickets sold at a zoo were child tickets

If the zoo sold 65 tickets in all then the zoo sold child tickets

The sum of 2 consecutive odd numbers is 248 Find the smaller number

Answer: The smaller number is ………

Which is the greatest 2-digit number divisible by 2, 3 and 4?

Answer: The number is ………

The sum of denominator and numerator of a fraction is 121and the fraction is equal to 4

7Find the denominator of the fraction?

The average of A, B, C is 48 and A is less than the sum of B and C

Find the value of A

Question 46:

Choose consecutively the cells with increasing value to remove them from the table.

ROUND 3 Question 1:

Choose consecutively the cells with increasing value to remove them from the table

6 people complete a task in 3 days How many people are needed to complete the same task

in 2 days? (everyone has the same productivity)

Convert: 4ton 15kg = ton

Write the result by decimal number with comma between number part and fraction part

The area of a rectangle is 7232cm2 The area of a circle is 5346cm2

The sum of area of this rectangle and this circle is dm2

Compare: A = 1,b5 + a,23 + 4,61c and B = a,b2c + 5,59

ROUND 5 Question 1:

Order the following in the ascending order:

Question 2:

Mrs Emily used 0,93kg of flour to make a cake

How much flour did she use to make 100 such cakes?

Answer: kg

Question 3:

The length of a rectangle is 2,36m and its width is 1,27m

The perimeter of this rectangle is m

Question 4:

Calculate: 19,7 x 6 =

Question 5:

Jane had 40 dollars She bought 5kg of mangoes at 4,55 dollars per kg

How much money did she have left?

Answer: dollars

Question 6:

1kg of apples costs 4,35 dollars and 1kg of grapes costs 7,2 dollars

How much money does Marie have to pay for 2kg of grapes and 3kg of apples?

The area of a rectangle is 24,7m2 If its length is decreased by 5 times and its width is

increased by 6 times then its area will equal m2

ROUND 6 Question 1: Choose 2 consecutive cells which have the same or equal value

Answer:

(1) = ; (2) = ; (3) = ; (6) = ; (7) = ; (9) = ; (11) = ; (13) = ; (14) = ; (16) =

Write these numbers in standard form: 21.3 = 20 + 1 + 0.3

Which of following is true?

A 149.34 = 100 + 40 + 9 + 0.34

B 127.06 = 120 + 7 + 0.06

C 105.9 = 100 + 5 + 0.9

Question 15:

This table shows the weights of Peter's three dogs

The product of the combined weight of Shadow and Josie and the weight of Brody is

ROUND 7 Question 1: Choose the increasing value

The table shows the cost of hamburgers:

If the pattern continues then the cost of 5 hamburgers is

Calculate the percentage: 70% of 48 is

Question 20:Complete the table below:

The missing number is

Question 24:

191 is a number that stays the same when read backwards as when read forwards How many

4 - digit numbers have this property?

Charlie buys two pairs of shoes for $15.75 each He gives the clerk $50.00

How much change should Charlie receive?

Anna buys a dress at a discount of 25% She spents 3

11 of her money to buy the dress and has

$450 left How much does the dress cost before the discount?

Question 34:

At a supermarket, a certain item has increased from 75 cents per pound to 87 cents per pound What is the percentage increase in the cost of the item?

Question 35:

There are 40 students in Mrs Jane’s class 20% of her students receive a B on the test How many students do not receive B?

ROUND 8 Question 1:

The number of centimetres in 7.05 metres is

Question 2:

The area of the figure shown is…

(All the sides are measured in the same units)

Question 7:

How many different 3-digit whole numbers can be formed using the digits 4, 5, 0 and 8, assuming that no digit can be repeated in a number?

Question 8:

At the beginning of the summer, Bob was 140 cm tall At the end of the summer, he

measured his height again and discovered that it had increased by 5% Measured in cm, what was his height at the end of summer?

Question 9:

Alice is going to the store One third of the way to the store, she stops to talk with Kelly She then continues for 6 km and reaches the store How many kilometres does she travel?

Question 10:

A bag contains green marbles and red marbles only If the ratio of the number of green

marbles to the number of red marbles is 1:4 then …… % of marbles are green

Question 21:

A motorbike at Store A costs $900 The regular price of the same motorbike at Store B is 10% more than it is at Store A The motorbike is on sale at Store B for 10% off of the regular price What is the sale price of the motorbike motorbike at Store B?

Question 22:

A clothing shop is having a 40% off sale How much would Jane have to pay for a $30

sweater with a discount?

ROUND 9 Question 1:

1.83 + … = 2 The missing number is …

Alice are going to buy sugar for her cooking class She need to have 1

6kg of sugar for every students in her class There are 18 students in her class How many kilogram of sugar should Alice buy?

Question 6:

Alice’s mathematics exam had 30 algebra Questions and 50 geometry Questions, each worth

1 mark She got 70% of the algebra Questions correct, and 60% of her Questions correct How many geometry Questions did she answer correctly?

The distance from Anna’s house to the store is 1

2 mile Anna run to the store twice a day, 7 days a week for 3 weeks How many miles does she run in total?

Question 18:

Peter and Jacob were running Both of them run with their constant speeds They started at the same time and the same place When Jacob reached the finishing line, Peter had only run of what Jacob had run Jacob’s speed is 75m/min (metre per minute) faster than Peter What was Peter’s speed in m/min?

Question 19:

The distance between John’s home and the park is 3000m John walked from his home to the park at a speed of 100m per minute and then walked back home at a speed of 150m per minute What is the John’s average speed in meter per minute?

Question 20:

Jack rides his horse with a constant speed of 12 miles per hour How far can he travel in hours?

Question 21:

A box contains 21 disks, each coloured red, blue and green There are twice as many green

disks as red disks, and half as many blue as red How many disks are red?

Question 22:

Charlie and Lily go on a 24 km run They both usually run at 9 km/h If Charlie runs at 2/3 his usual running speed, and Lily runs at 4/3 times her usual speed, how many more hours does it take Charlie to complete the run than it takes Lily to complete the run?

Question 23:

Each face of a cube is painted with exactly one colour What is the smallest number of

colours needed to paint a cube so that no two faces that share an edge are the same colour?

ROUND 10 Question 1:

How fast is Anna going if she runs 8 miles in the park in only 2 hours?

The distance between 2 trees is 300 meters It will take a bird 30 seconds to fly between these

2 trees How fast is the bird in kilometer per hour?

What is the difference between the sum of the first 2016 even natural numbers, and the first

2016 odd natural numbers?

Question 12:

12 hours 24 minutes 2 =…………hours

(Write your answer by decimal in the simplest form)

Jack buys 25 sofas from a wholesale market for $3750, and then he sells all of them at a loss

of 4% How much money did he sell each sofa for?

1.4 Arrange the values in ascending order (sắp xếp theo thứ tự tăng dần)

Definition: triangle (tam giác), base (đáy), height (chiều cao), trapezium (hình thang),

circle (hình tròn), circumference (chu vi hình tròn), radius (bán kính), area (diện tích), perimeter (chu vi), cuboid (hình hộp chữ nhật), cube (hình lập phương), total surface area (diện tích toàn phần), volume (thể tích)

2.1 Find the area of a triangle with base equal 42.5cm and height equal 5.2cm

2.2 To make a triangular road sign needs 22.4dm2 of metal Its height is 54cm Find the corresponding base of the sign

2.3 A trapezium has 2 bases: 9.4m and 6.6m; and the height is 10.5m Find the area in square meter

2.4 A trapezium-shaped garden has the average of 2 bases equal 125dm and the height is 150dm Find the area of the garden in square meter

2.5 A circular well has radius equal 3.2dm Find the circumference of the well

2.6 A trapezium-shaped field has the long base equal 150m and the short base equal 3

5 of the long base The height equals to the average of 2 bases People grow rice on the field and harvest 65kg of rice in every 100m2 In total, how many tons of rice can be harvested in the field?

2.7 Find the total surface area of a cube with its side equal to 7.2dm

2.8 Cubes with side equal 1cm are used to build a cuboid of 12cm x 8cm x 6cm How many cubes are needed?

2.9 Each brick is 30cm long, 20cm wide and 0.5cm high Each box contains 24 bricks Find the volume of the box

2.10 960 cubes with side equal 1cm are arranged as a cuboid with 12cm in length and 10cm in width 6 faces of the cuboid are painted How many cubes are painted in only 1 face?

3 Phần trăm

Definition: percent (phần trăm), percentage (tỉ số phần trăm)

3.1 20% of a number equals 9.5 What is the number?

3.2 In a regular Math test, 72.5% of class 5A students got Excellent score, 20% got Good score and the other 3 students got Average score How many students got Excellent score?

3.3 57.5% of class 5E students are girls The number of boys has 6 students less than that

of girls How many students are there in class 5E?

3.4 In semester I, 90% of students got Good score The principal thought that if 45 more students got Good score, there would be 95% of students getting Good score How many students got Good score in semester I?

3.5 Cube A has its side equal 2 times of the side of cube B Find the percentage between cube B’s total surface area and cube A’s

3.6 In order to increase the volume of a cuboid tank, people increase the length of the tank and keep the width and the height unchanged The area of the base increases by 75% and the tank can contain 1500 more liters of water Find the volume of the tank before change?

3.7 55% of students in a school are boys The number of boys is 120 more than that of girls How many students in the school?

3.8 In an event, a shop discounted a phone’s price by 10% and still got 8% profit If the shop had not discounted the phone’s price, how much would the profit have been? 3.9 In 3 days, a group of workers fixed a road of 3km50m On day 1, the group fixed 30% of the road, on day 2, the group fixed 45% of the road What is the length of the road did the group fix on day 3?

3.10 If the length of a rectangle increases by 25%, how many percent does the width decrease so that the area is unchanged?

4 Tổng – Hiệu – Tỉ số

Definition: sum (tổng), difference (hiệu), ratio (tỉ số)

4.1 Sum of 2 number equals 86.25 1

2 of the first number equals

1

3 of the second number Find the first number

4.2 A factory has 2 stores 1

5 of the first store’s goods equals

1

3 of the second one’s How many tons of goods are there in 2 stores given that the difference of goods between 2 stores is 39 tons?

4.3 Sum of 2 numbers is 218 If the smaller number plus 5 and the larger number plus 9,

the ratio of 2 new numbers is 3

5 Find the larger number

4.4 Sum of 2 numbers is 136.5 The first number times 0.6 equals the second one times 0.8 Find the first number

4.5 3 classes 5A, 5B and 5C receive a number of books 5A gets 1

3 of the books and 5

books; 5B gets 1

4 of the books and 27 books and the rest of 118 books belong to 5C How many books does 5A get?

4.6 Sum of 2 numbers is 340.8 and the ratio is 3

5 Find the smaller number

4.7 Difference of 2 numbers is 114.9 and the ratio is 5

8 Find the larger number

4.8 Difference of 2 numbers is 87.6 and the ratio is 3

5 Find the smaller number

4.9 A rectangular field has perimeter of 480m and the width equals 3

5 of the length Find the length

5 Vận tốc

Definition: distance (khoảng cách), time (thời gian), speed (tốc độ)

5.1 At 6:15, a person travels from A to B He arrives B at 9:15 and the distance AB is 135km What is his speed?

5.2 It takes 2 hours for a car to travel from A to B at 50km/h How long does it take for a motorbike to travel from A to B at 40km/h?

5.3 A car travels from A to B in 5 hours During the first 2 hours, the car’s speed is 40km/h and during the last 3 hours, the car’s speed is 50km/h Find the average speed

of the car

5.4 After school, Lan walks back home at speed of 4km/h After 15 minutes, her father picks her up and gets back home at speed of 40km/h How long is it from Lan’s house to school? Given that her father takes her back home in 6 minutes

5.5 A car travels 90km in 1.5 hours How long does it take for the car to travel 135km at the same speed?

5.6 At 7:00, a motorbike travels from A to B at 40km/h At the same time, a car travels from B to A at 45km/h What time do they meet each other given that distance AB is 127.5km?

5.7 A car travels from A, passing B to C At the same time, a motorbike travel from B to

C After 3 hours 48 minutes, the car meets the motorbike AB is 102.6km and the

car’s speed is 5

3 of the motorbike’s Find the speed of the car

5.8 Distance AB is 120km At 5:00, a car travels from A to B in 2 hours and 30 minutes

At the same time, a motorbike travels from A to B at the speed equal 2

5 of the car’s How long, after the car arrives B, does the motorbike arrive B?