Opal and Sabrina collected pens. Opal gave 25% of her pens to Sabrina. As a result, Sabrina's pens increased by 60%. If Opal had 63 pens left, find the total number of pens the two girls had at first.
| |
Opal |
Sabrina |
Comparing the change
in Sabrina's pens |
| Before |
4x3 =
12 u |
|
5x1 =
5 u |
| Change |
- 1x3 =
- 3 u |
+ 1x3 =
+ 3 u |
+ 3x1 =
+ 3 u |
| After |
3x3 =
9 u |
|
8x1 =
8 u |
25% =
25100 =
14 60% =
60100 =
35 The number of pens that Opal gave to Sabrina is repeated. Make the number of pens that Opal gave to Sabrina the same. LCM of 1 and 3 is 3.
Number of pens that Opal had in the end = 9 u
9 u = 63
1 u = 63 ÷ 9 = 7
Number of pens that Opal and Sabrina had at first
= 12 u + 5 u
= 17 u
= 17 x 7
= 119
Answer(s): 119
