14 days ago, Fiona had a total of 300 yellow and brown cards. 25% of her cards were brown cards. Today, her grandfather gave her some more cards. As a result, her yellow cards increased by 40%. Now, 50% of her cards are brown cards. How many brown cards did her grandfather give her?
| |
Brown cards |
Yellow cards |
Total
cards |
| Before |
1 u |
3 u |
300 |
| Change |
+ 3.2 u |
+ 1.2 u |
|
| After |
4.2 u |
4.2 u |
|
Comparing the
yellow cards and
brown cards in the end |
1 |
1 |
|
25% =
25100 =
14 Brown cards : Yellow cards = 1 : 3
Increase in the number of yellow cards
= 40% x 3 u
=
40100 x 3 u
= 1.2 u
50% =
50100 =
12 In the end
Brown cards : Yellow cards = 1 : 1
Number of cards at first
= 3 u + 1 u
= 4 u
4 u = 300
1 u = 300 ÷ 4 = 75
Number of brown cards that Fiona received from her grandfather
= 4.2 u - 1 u
= 3.2 u
= 3.2 x 75
= 240
Answer(s): 240
