Jaslyn had some card collection.
37 of them were pink and the rest were black. She gave away 198 of the black cards and 10% of the pink cards. She then had
14 of her card collection left. How many cards did Jaslyn give away?
| |
Pink |
Black |
Total |
Total |
Before
|
3x4 =
12 u |
4x4 =
16 u |
7x4 =
28 u |
4x7 =
28 u |
Change
|
- 0.3x4 =
- 1.2 u |
- 198 |
|
- 3x7 =
- 21 u |
After
|
2.7x4 =
10.8 u |
16 u - 198 |
|
1x7 =
7 u |
The total number of cards that Jaslyn had at first is repeated. Make the total number of cards at first the same. LCM 7 and 4 is 28.
Number of pink cards that Jaslyn gave away
= 10% x 3 u
=
10100 x 3 u
= 0.3 u
1.2 u - 198 = 21 u
21 u - 1.2 u = 198
19.8 u = 198
1 u = 198 ÷ 19.8 = 10
Number of cards that Jaslyn gave away
= 21 u
= 21 x 10
= 210
Answer(s): 210
