PSLE Cathy had 60 post-it notes and Zara had 31 post-it notes. After Cathy gave some of her post-it notes to Zara, the number of post-it notes Cathy and Zara had was in the ratio 3 : 4. How many post-it notes did Cathy have in the end?
|
Cathy |
Zara |
Total |
Before |
60 |
31 |
91 |
Change |
- ? |
+ ? |
|
After |
3 u |
4 u |
7 u |
Total number of post-it notes
= 60 + 31
= 91
Total number of post-it notes
= 3 u + 4 u
= 7 u
7 u = 91
1 u = 91 ÷ 7 = 13
Number of post-it notes that Cathy had in the end
= 3 u
= 3 x 13
= 39
Answer(s): 39