4 days ago, Gabby had a total of 225 gold and pink buttons. 40% of her buttons were pink buttons. Today, her younger sister gave her some more buttons. As a result, her gold buttons increased by 20%. Now, 50% of her buttons are pink buttons. How many pink buttons did her younger sister give her?
| |
Pink buttons |
Gold buttons |
Total
buttons |
| Before |
2 u |
3 u |
225 |
| Change |
+ 1.6 u |
+ 0.6 u |
|
| After |
3.6 u |
3.6 u |
|
Comparing the
gold buttons and
pink buttons in the end |
1 |
1 |
|
40% =
40100 =
25 Pink buttons : Gold buttons = 2 : 3
Increase in the number of gold buttons
= 20% x 3 u
=
20100 x 3 u
= 0.6 u
50% =
50100 =
12 In the end
Pink buttons : Gold buttons = 1 : 1
Number of buttons at first
= 3 u + 2 u
= 5 u
5 u = 225
1 u = 225 ÷ 5 = 45
Number of pink buttons that Gabby received from her younger sister
= 3.6 u - 2 u
= 1.6 u
= 1.6 x 45
= 72
Answer(s): 72
