Julie had 100 pens.
910 of them were blue pens and the rest were grey pens. After she had given away some blue pens, the ratio of the number of blue pens to the number of grey pens became 3 : 5. How many pens did she have in the end?
| |
Blue |
Grey |
Total |
| Before |
9x5 =
45 u |
1x5 =
5 u |
10x5 =
50 u |
| Change |
- 42 u |
|
|
| After |
3 u |
5 u |
8 u |
The number of grey pens remained unchanged.
LCM of 1 and 5 = 5
Total number of pens at first = 50 u
50 u = 100
1 u = 100 ÷ 50 = 2
Number of pens that Julie had in the end
= 3 u + 5 u
= 8 u
= 8 x 2
= 16
Answer(s):16
