10 days ago, Opal had a total of 250 silver and pink buttons. 20% of her buttons were pink buttons. Today, her grandfather gave her some more buttons. As a result, her silver buttons increased by 30%. Now, 50% of her buttons are pink buttons. How many pink buttons did her grandfather give her?
| |
Pink buttons |
Silver buttons |
Total
buttons |
| Before |
1 u |
4 u |
250 |
| Change |
+ 4.2 u |
+ 1.2 u |
|
| After |
5.2 u |
5.2 u |
|
Comparing the
silver buttons and
pink buttons in the end |
1 |
1 |
|
20% =
20100 =
15 Pink buttons : Silver buttons = 1 : 4
Increase in the number of silver buttons
= 30% x 4 u
=
30100 x 4 u
= 1.2 u
50% =
50100 =
12 In the end
Pink buttons : Silver buttons = 1 : 1
Number of buttons at first
= 4 u + 1 u
= 5 u
5 u = 250
1 u = 250 ÷ 5 = 50
Number of pink buttons that Opal received from her grandfather
= 5.2 u - 1 u
= 4.2 u
= 4.2 x 50
= 210
Answer(s): 210
