Lynn and Sarah collected pens. Lynn gave 40% of her pens to Sarah. As a result, Sarah's pens increased by 75%. If Lynn had 18 pens left, find the total number of pens the two girls had at first.
| |
Lynn |
Sarah |
Comparing the change
in Sarah's pens |
| Before |
5x3 =
15 u |
|
4x2 =
8 u |
| Change |
- 2x3 =
- 6 u |
+ 2x3 =
+ 6 u |
+ 3x2 =
+ 6 u |
| After |
3x3 =
9 u |
|
7x2 =
14 u |
40% =
40100 =
25 75% =
75100 =
34 The number of pens that Lynn gave to Sarah is repeated. Make the number of pens that Lynn gave to Sarah the same. LCM of 2 and 3 is 6.
Number of pens that Lynn had in the end = 9 u
9 u = 18
1 u = 18 ÷ 9 = 2
Number of pens that Lynn and Sarah had at first
= 15 u + 8 u
= 23 u
= 23 x 2
= 46
Answer(s): 46
