13 days ago, Lynn had a total of 280 blue and silver beads. 25% of her beads were silver beads. Today, her younger brother gave her some more beads. As a result, her blue beads increased by 20%. Now, 50% of her beads are silver beads. How many silver beads did her younger brother give her?
| |
Silver beads |
Blue beads |
Total
beads |
| Before |
1 u |
3 u |
280 |
| Change |
+ 2.6 u |
+ 0.6 u |
|
| After |
3.6 u |
3.6 u |
|
Comparing the
blue beads and
silver beads in the end |
1 |
1 |
|
25% =
25100 =
14 Silver beads : Blue beads = 1 : 3
Increase in the number of blue beads
= 20% x 3 u
=
20100 x 3 u
= 0.6 u
50% =
50100 =
12 In the end
Silver beads : Blue beads = 1 : 1
Number of beads at first
= 3 u + 1 u
= 4 u
4 u = 280
1 u = 280 ÷ 4 = 70
Number of silver beads that Lynn received from her younger brother
= 3.6 u - 1 u
= 2.6 u
= 2.6 x 70
= 182
Answer(s): 182
