PSLEBetty had a collection of stamps from Mexico, Ireland and Thailand. She had 81 stamps from Mexico. 40% of her stamps were from Ireland. She had 21 fewer stamps from Thailand than from Ireland.
- What was the total number of stamps in Betty's collection?
- Betty's aunt gave her some stamps from Ireland. Her total collection increased by 25%. What percentage of her collection was from Ireland after that?
(a)
Mexico |
Ireland |
Thailand |
Total |
81 |
40% |
40% - 21 |
100% |
|
+ 25% |
|
+ 25% |
|
65% |
|
125% |
Total number of stamps
= 40% + 40% - 21 + 81
= 80% + 60
100% = 80% + 60
100% - 80% = 60
20% = 60
1% = 60 ÷ 20 = 3
Total number of stamps in Betty's collection
= 100%
= 100 x 3
= 300
(b)
Old stamp collection = 100%
New stamp collection = 100% + 25% = 125%
Percentage of stamps from Ireland
= 40% + 25%
= 65%
Percentage of her collection from Ireland
=
65125 x 100%
= 52%
Answer(s): (a) 300; (b) 52%