Answer:

Step-by-step explanation:
Let the total number of students = x,
∴ Number of boys = 40% of x = 0.4x,
So, the number of girls = students - boys
= x - 0.4x
= 0.6x
Now, 50% of the boys chosen blue as their favourite colour,
So, the number of boys whose favourite colour is blue = 50% of 0.4x
= 0.50 × 0.4x
= 0.2x,
Now, 20% of the girls chosen blue as their favourite colour,
So, the number of girls whose favourite colour is blue = 20% of 0.6x
= 0.20 × 0.6x
= 0.12x
Thus, the total students who like blue colour = 0.20x + 0.12x = 0.32x
Also, the fraction of the boys whose favourite colour is blue out of the total students who like blue

