5 days ago, Dana had a total of 100 white and pink beads. 20% of her beads were pink beads. Today, her younger sister gave her some more beads. As a result, her white beads increased by 30%. Now, 50% of her beads are pink beads. How many pink beads did her younger sister give her?
| |
Pink beads |
White beads |
Total
beads |
| Before |
1 u |
4 u |
100 |
| Change |
+ 4.2 u |
+ 1.2 u |
|
| After |
5.2 u |
5.2 u |
|
Comparing the
white beads and
pink beads in the end |
1 |
1 |
|
20% =
20100 =
15 Pink beads : White beads = 1 : 4
Increase in the number of white beads
= 30% x 4 u
=
30100 x 4 u
= 1.2 u
50% =
50100 =
12 In the end
Pink beads : White beads = 1 : 1
Number of beads at first
= 4 u + 1 u
= 5 u
5 u = 100
1 u = 100 ÷ 5 = 20
Number of pink beads that Dana received from her younger sister
= 5.2 u - 1 u
= 4.2 u
= 4.2 x 20
= 84
Answer(s): 84
