15 days ago, Diana had a total of 175 pink and yellow buttons. 20% of her buttons were yellow buttons. Today, her younger sister gave her some more buttons. As a result, her pink buttons increased by 10%. Now, 50% of her buttons are yellow buttons. How many yellow buttons did her younger sister give her?
| |
Yellow buttons |
Pink buttons |
Total
buttons |
| Before |
1 u |
4 u |
175 |
| Change |
+ 3.4 u |
+ 0.4 u |
|
| After |
4.4 u |
4.4 u |
|
Comparing the
pink buttons and
yellow buttons in the end |
1 |
1 |
|
20% =
20100 =
15 Yellow buttons : Pink buttons = 1 : 4
Increase in the number of pink buttons
= 10% x 4 u
=
10100 x 4 u
= 0.4 u
50% =
50100 =
12 In the end
Yellow buttons : Pink buttons = 1 : 1
Number of buttons at first
= 4 u + 1 u
= 5 u
5 u = 175
1 u = 175 ÷ 5 = 35
Number of yellow buttons that Diana received from her younger sister
= 4.4 u - 1 u
= 3.4 u
= 3.4 x 35
= 119
Answer(s): 119
