11 days ago, Jaslyn had a total of 140 brown and pink stamps. 40% of her stamps were pink stamps. Today, her younger sister gave her some more stamps. As a result, her brown stamps increased by 25%. Now, 50% of her stamps are pink stamps. How many pink stamps did her younger sister give her?
| |
Pink stamps |
Brown stamps |
Total
stamps |
| Before |
2 u |
3 u |
140 |
| Change |
+ 1.75 u |
+ 0.75 u |
|
| After |
3.75 u |
3.75 u |
|
Comparing the
brown stamps and
pink stamps in the end |
1 |
1 |
|
40% =
40100 =
25 Pink stamps : Brown stamps = 2 : 3
Increase in the number of brown stamps
= 25% x 3 u
=
25100 x 3 u
= 0.75 u
50% =
50100 =
12 In the end
Pink stamps : Brown stamps = 1 : 1
Number of stamps at first
= 3 u + 2 u
= 5 u
5 u = 140
1 u = 140 ÷ 5 = 28
Number of pink stamps that Jaslyn received from her younger sister
= 3.75 u - 2 u
= 1.75 u
= 1.75 x 28
= 49
Answer(s): 49
