2
2. The answer to
5 2 4
3 − + ×
is A
B C
D E
12 15
17 19
20 ANSWER: B
5 2
4 3
3 12 15
− + ×
= + =
3. If
n =
5
then the value of 7
5 5 3
5 n
n n
− −
+ is
A B
C D
E 50
500 5000
50000 ANSWER: A
7 5
5 3 5
7 5 5 5 5 3 5
5 5 5 5
n n
n n
− −
+ = −
− + =
− = − = since
4. An ant covers a distance of 90 metres in 3 hours.
The average speed of the ant in centimetres per minute is A
B C
D E
30 40
50 60
70 ANSWER: C
distance time minutes
Average speed distance
time min
cm
cm =
× =
= × =
= =
= 90 10
9 000 3
60 180 9 000
180 50
5.
Given that 9
25 0 36
= ,
then 0 9
0 25 ,
, is equal to
A B
C 3
D 36 E
360 0 036
0 36 6
, ,
, ANSWER: C
0 9 0 25
0 9 100
0 25 100 90
25 9
25 10
0 36 10 3 6
, ,
, ,
, ,
= ×
× =
= ×
= ×
=
3
6. A square is divided into 4 identical rectangles
as shown in the diagram. The perimeter of each of the four rectangles is 30 units.
What is the perimeter of the square?
A B
C D
E 36
40 44
48 52
ANSWER: D 4
2 2
2 4 2
10 10
30 3
12 4
4 12 48
× = = +
= × +
= =
∴ = ∴ =
= =
= b
l l
b b
b b
b b
l l
Perimeter of A
Perimeter of square
7.
Allison, Nomsa and Jan shared a sum of money in the ratio of 4 : 3 : 1 respectively. Allison received R70 more than Nomsa.
The total amount that was shared initially was
A R640
B R
C R
D R E
R 560
480 400
320 ANSWER: B
Allison : Nomsa : Jan 4
: 3 : 1 Total number of parts = 4 + 3 + 1 = 8
Difference between Allison and Nomsa: 1 part = R70 ∴
= × =
Total amount R
R 8
70 560
A
l b
b b
b
l
4
8. Which of the following nets will
NOT form a closed triangular prism?
ANSWER: C The net of C has 2 triangular ‘ends’
at the same side. The prism will therefore not be closed.
9. The product of two numbers is 504 and each of the numbers is divisible by 6.
Neither of the two numbers is 6. What is the larger of the two numbers? A
B C
D E
48 84
72 60
42 ANSWER: E
2 504 2 252
2 126 3 63
3 21 7 7
1
10. Two windmills pour water into a 1 000 tank. One windmill pours water into
the tank at a rate of 20 per minute. The other windmill pours water into the tank at 20 in 3 minutes. How many minutes will it take to fill the tank?
A B
C D
E 37
1 2
75 112
1 2
150 175
ANSWER: A Windmill 1: rate = 20 min.
Windmill 2: rate = 20 3 min = 6,667 min Windmill 1 + Windmill 2: rate = 26,667 min
Volume of tank: 1 000
A B
C
D E
∴ =
× × × × ×
= ×
504 2
3 2
2 3
7 12
42
5
time volume
rate =
=
= 1 000
26 667 37
1 2
, min
min
Or
Time Windmill 1
Windmill 2 Total
rate: 20 min rate: 20 3 min
After 50 min 1 000
+ 333,3
= 1 333,3 After 40 min
800 +
266,7 = 1 066,7
After 30 min 600
+ 200 =
800 After 35 min
700 +
233,3 = 933,3
After 37,5 min 750
+ 250
= 1 000
Or
Volume of the tank = 1000 Windmill 1: rate = 20 min
Windmill 2: rate = 20 3 min For both windmills we have
20 1
20 3
80 3
min min
min +
= Let the time taken to fill a 1000 tank be x.
i.e. tempo: 1000
x Now
1000 80
3 1000
3 80
300 8
37 5 x
x =
∴ = ×
= =
min min
.min , min
11.
The Ancient Romans used the following different numerals in their number system:
Note: Tank 1
Tank 2
Min 1: 20 Min 2: 20
Min 3: 20 20 60
20
6
I C
V D
X M
etc. L
= =
= =
= =
= 1
100 5
500 10
1 000 50
, They used these numerals to make up numbers as follows:
I VI
II VII
III VIII
IV IX
V X
etc. =
= =
= =
= =
= =
= 1
6 2
7 3
8 4
9 5
10, So, for example, XCIX is 99. What is the value of XLVI?
A B
C D
E 42
44 46
64 66
ANSWER: C L = 50
XL = 40 i.e. 10 from 50 = 40 VI = 6 i.e. 1 added to 5 = 6
XLVI = 46
12. Did you know?
