Question:
The number of blue pens that Mrs Li had was 6/5 of the number of red pens. Her son took 52 red pens and 24 blue pens from her. After that, the number of red pens became 1/6 of the number of blue pens. How many blue pens did Mrs Li have in the end?
Solution:
![P6 / ACS / 2019 / CA1 – Q21 [4 marks]](https://i0.wp.com/sgprimaths.com/wp-content/uploads/2021/01/P6_ACS_2019_CA1_Q21-Qns.jpg?resize=400%2C260&ssl=1)