Roshel had some card collection.
38 of them were black and the rest were pink. She gave away 106 of the pink cards and 30% of the black cards. She then had
23 of her card collection left. How many cards did Roshel give away?
| |
Black |
Pink |
Total |
Total |
Before
|
3x3 =
9 u |
5x3 =
15 u |
8x3 =
24 u |
3x8 =
24 u |
Change
|
- 0.9x3 =
- 2.7 u |
- 106 |
|
- 1x8 =
- 8 u |
After
|
2.1x3 =
6.3 u |
15 u - 106 |
|
2x8 =
16 u |
The total number of cards that Roshel had at first is repeated. Make the total number of cards at first the same. LCM 8 and 3 is 24.
Number of black cards that Roshel gave away
= 30% x 3 u
=
30100 x 3 u
= 0.9 u
2.7 u - 106 = 8 u
8 u - 2.7 u = 106
5.3 u = 106
1 u = 106 ÷ 5.3 = 20
Number of cards that Roshel gave away
= 8 u
= 8 x 20
= 160
Answer(s): 160
