Elyse had some pen collection.
12 of them were black and the rest were pink. She gave away 165 of the pink pens and 50% of the black pens. She then had
13 of her pen collection left. How many pens did Elyse give away?
| |
Black |
Pink |
Total |
Total |
Before
|
1x3 =
3 u |
1x3 =
3 u |
2x3 =
6 u |
3x2 =
6 u |
Change
|
- 0.5x3 =
- 1.5 u |
- 165 |
|
- 2x2 =
- 4 u |
After
|
0.5x3 =
1.5 u |
3 u - 165 |
|
1x2 =
2 u |
The total number of pens that Elyse had at first is repeated. Make the total number of pens at first the same. LCM 2 and 3 is 6.
Number of black pens that Elyse gave away
= 50% x 1 u
=
50100 x 1 u
= 0.5 u
1.5 u - 165 = 4 u
4 u - 1.5 u = 165
2.5 u = 165
1 u = 165 ÷ 2.5 = 66
Number of pens that Elyse gave away
= 4 u
= 4 x 66
= 264
Answer(s): 264
