SASMO 2018 Primary 5 (Grade 5) Contest

Question 1

Calculate $46\times22+37\times22+17\times22$.

1. 220
2. 660
3. 2200
4. 6600
5. None of the above

Question 2

A fractal tree starts with 6 branches. At each new step, 6 new branches grow from every branch formed in the previous step. How many new branches are obtained in step 6?

1. $6\times6\times6\times6\times6$
2. $6\times6\times6\times6\times6\times6$
3. $6^7$
4. $36\times36$
5. $36^4$

Question 3

Trees are planted on one side of Liang Street, 8 m apart, including both ends. If there are 21 trees, how long is the street?

1. 152 m
2. 160 m
3. 168 m
4. 176 m
5. None of the above

Question 4

Figures 1, 2 and 3 contain 5, 10 and 17 small squares. Continuing the pattern, how many small squares are in Figure 20?

1. 422
2. 440
3. 442
4. 444
5. None of the above

Question 5

Two trains leave the same station at the same time in opposite directions at 250 km/h and 300 km/h. How far apart are they after 3 hours?

1. 150 km
2. 450 km
3. 1350 km
4. 1650 km
5. None of the above

Question 6

A bar chart shows cars in Carparks A-D, totaling 156. Find the difference between the greatest and smallest carpark counts.

1. 60
2. 65
3. 70
4. 75
5. None of the above

Question 7

A date is a Factor Day if month number multiplied by day equals the last two digits of the year. How many Factor Days are there from 1 January 2015 through 31 December 2019?

1. 9
2. 10
3. 12
4. 14
5. 15

Question 8

Find the next fraction in $\frac13,\frac12,\frac59,\frac7{12},\frac35,\ldots$

1. $\frac{17}{18}$
2. $\frac{11}{18}$
3. $\frac5{18}$
4. $\frac57$
5. None of the above

Question 9

What percentage of the whole triangle is shaded?

1. 4%
2. 16%
3. 20%
4. 25%
5. 40%

Question 10

Find the sum of the perimeters of the three rectangles shown.

1. 38 cm
2. 40 cm
3. 42 cm
4. 44 cm
5. None of the above

Question 11

Carrots in Billy's cage to Phil's cage were in ratio $3:4$. After carrots were transferred from Phil to Billy, the ratio became $2:1$. What is the smallest possible number transferred?

1. 2
2. 3
3. 4
4. 5
5. None of the above

Question 12

Find digit $X$ so that the four-digit number $37XX$ is divisible by 12.

1. 0
2. 2
3. 4
4. 6
5. 8

Question 13

Arrange triangles A, B, C and D from smallest to largest area.

1. A, B, C, D
2. B, C, A, D
3. D, C, A, B
4. D, A, C, B
5. None of the above

Question 14

Amy, Bob, Chris and Doris are either truth-tellers or liars. Amy says exactly one is a liar; Bob says exactly two; Chris says exactly three; Doris says all four. If at least one statement is true, which tribes do they belong to?

1. A and B truth-tellers; C and D liars
2. B and C truth-tellers; A and D liars
3. A and C truth-tellers; B and D liars
4. Chris truth-teller; Amy, Bob, Doris liars
5. Chris and Doris truth-tellers; Amy and Bob liars

Question 15

The cube shown was split into Figures 1, 2 and 3. Which option is the missing Figure 3?

1. Figure A
2. Figure B
3. Figure C
4. Figure D
5. Figure E

Question 16

Find the number represented by the heart if $\star+\star+\heartsuit+\star+\heartsuit=57$ and $\heartsuit+\star+\star+\heartsuit+\heartsuit=68$.

Question 17

Find the number of triangles in the figure.

Question 18

How many three-digit numbers have hundreds digit plus tens digit equal to the ones digit? For example, 527 because $5+2=7$.

Question 19

Orange soda is sold in boxes of 9 cans for 8 dollars per box. One free can is given for every 2 boxes bought, and 5 empty cans can be exchanged for 1 free can. What is the greatest number of cans obtainable with 40 dollars?

Question 20

If 4 spiders build 12 webs in 10 minutes, how long do 16 spiders take to build 24 webs?