21
Percentages
1
The screen shot shows the calculator converting 25% to a fraction.
Enter 25% by pressing
25
SHIFT
(
followed by
p
to check the value of
25% as a fraction.
2
Express each percentage as a fraction.
A
50%
B
75%
C
40%
D
5%
E
100%
F 200%
G
1
2
%
H
1.5%
I
1
4
%
J
35%
3
Express each percentage as a decimal.
Hint!
Express the percentage as a fraction then press the
n
button.
A
45%
B
79%
C
5%
D
7.5%
E
1
2
2
%
F 245%
G
1000%
H
1%
I
120.5%
J
1
11
2
%
4
The screen shot shows the solution to the problem ‘Increase 40 by 10%’.
Check the calculation by pressing
40+10
SHIFT
(O40p
.
Determine the following amounts.
A
Increase 60 by 10%.
B
Increase 75 by 25%.
C
Decrease 80 by 20%. (Hint! Remember decrease means make smaller.)
D
Decrease $120 by 30%.
E
Increase $90 by 25% then decrease the result by 25%.
5
The local sports store is having a ‘15% off sale’. Gillian is going to buy a pair of
running shoes that normally cost $165. How much will the running shoes cost in
the ‘15% off sale’?
Answers
2A
1
2
B
3
4
C
2
5
D
1
20
E
1
F
2
G
1
200
H
3
200
I
1
400
J
7
20
3A
0.45
B
0.79
C
0.05
D
0.075
E
0.025
F
2.45
G
10
H
0.01
I
1.205
J
0.115
4A
66
B
93.75
C
64
D
$84
E
84.375
5
$140.25
© Sue Thomson and Shriro Australia PTY Limited. This page may be photocopied for classroom use.