SASMO 2015 Primary 3 (Grade 3) Contest

Question 1

Find the missing term in the following sequence: $1,2,4,7,\underline{\hspace{8mm}},16$.

1. 10
2. 11
3. 12
4. 13
5. 14

Question 2

$2^5$ means 2 multiplied by itself 5 times, i.e. $2^5=2\times2\times2\times2\times2=32$. What is $3^4$ equal to?

1. 7
2. 12
3. 27
4. 81
5. None of the above

Question 3

An operator $*$ acts on two numbers as follows: $3*2=51$, $5*3=82$, $6*1=75$, and $9*4=135$. What is $7*5$ equal to?

1. 112
2. 121
3. 122
4. 212
5. None of the above

Question 4

The diagram shows a figure that contains 7 identical squares. The area of the figure is $112\text{ cm}^2$. Find its perimeter.

1. 56 cm
2. 60 cm
3. 64 cm
4. 68 cm
5. 72 cm

Question 5

Fill in the blank: $\underline{\hspace{1cm}}$ is 4 tens 5 ones greater than 2 tens 7 ones.

1. 18
2. 28
3. 62
4. 72
5. None of the above

Question 6

Which of the following statements is or are correct?

A: $7+(0\times2)=7$

B: $7+(0\div2)=7$

C: $7+(2\times0)=7$

1. All three statements are correct.
2. Only A and B are correct.
3. Only A and C are correct.
4. Only B and C are correct.
5. None of the above.

Question 7

There are 4 types of cakes in a cake shop: chocolate, cheese, blueberry and black forest. Naomi wants to buy 2 different types. How many different choices does she have?

1. 4
2. 6
3. 8
4. 10
5. 12

Question 8

Find the total number of squares in a $3\times3$ square grid.

1. 9
2. 10
3. 13
4. 14
5. 15

Question 9

Find the smallest whole number between 14 and 40 that is divisible by both 3 and 4.

1. 12
2. 16
3. 18
4. 24
5. 36

Question 10

What is the side length of the largest square that can be made from 50 one-centimetre square tiles?

1. 5 cm
2. 6 cm
3. 7 cm
4. 8 cm
5. None of the above

Question 11

Two numbers satisfy these conditions: the first number is at least 5 and at most 8; the second number is at least 2 and at most 10. Find the least possible value of their sum.

Question 12

If the four-digit number $12N4$ is divisible by 3 and $N$ is less than 5, find $N$.

Question 13

A whole number multiplied by itself gives a special type of number called a perfect square. For example, $9=3\times3$ and $16=4\times4$. What is the smallest number that can be multiplied by 28 to give a perfect square?

Question 14

Find the day of the week that is 50 days after a Monday.

Question 15

Amy wants to cut rectangular cards measuring 4 cm by 3 cm from a rectangular sheet measuring 32 cm by 21 cm. Find the greatest number of cards that can be cut from the sheet.

Question 16

Five items—a ruler, a pen, an eraser, a sharpener and a hole puncher—lie in a straight row. The eraser is next to both the hole puncher and the sharpener. The ruler is next to the hole puncher. The sharpener is the first item on the left. What is the order from left to right?

Question 17

In the following alphametic, different letters stand for different digits. Find the two-digit number $NO$.

$$\begin{array}{r}NON\\-\ AN\\\hline NO\end{array}$$

Question 18

Fifty cakes are packed in two box sizes. A small box holds 4 cakes and a big box holds 6 cakes. If fewer than 10 boxes are used and every box is full, how many big boxes are used?

Question 19

Alice and Ben are sister and brother. Alice has as many sisters as brothers, while Ben has twice as many sisters as brothers. How many boys and girls are there in their family?

Question 20

The diagram shows a rectangle divided into 3 smaller rectangles and a square. If the perimeter of the unshaded rectangle is 16 cm and the area of the square is $9\text{ cm}^2$, find the total area of the shaded rectangles.