PSLEIrene had a collection of stamps from Australia, Norway and Kenya. She had 172 stamps from Australia. 10% of her stamps were from Norway. She had 12 fewer stamps from Kenya than from Norway.
- What was the total number of stamps in Irene's collection?
- Irene's aunt gave her some stamps from Norway. Her total collection increased by 20%. What percentage of her collection was from Norway after that?
(a)
Australia |
Norway |
Kenya |
Total |
172 |
10% |
10% - 12 |
100% |
|
+ 20% |
|
+ 20% |
|
30% |
|
120% |
Total number of stamps
= 10% + 10% - 12 + 172
= 20% + 160
100% = 20% + 160
100% - 20% = 160
80% = 160
1% = 160 ÷ 80 = 2
Total number of stamps in Irene's collection
= 100%
= 100 x 2
= 200
(b)
Old stamp collection = 100%
New stamp collection = 100% + 20% = 120%
Percentage of stamps from Norway
= 10% + 20%
= 30%
Percentage of her collection from Norway
=
30120 x 100%
= 25%
Answer(s): (a) 200; (b) 25%