90 students take a test. The ratio of boys to girls is 3:2.
One third of the boys score full marks.
The number of girls scoring full marks is half the number who do not score full marks.

Step-by-step explanation:

If there are 90 students and the ratio of boys to girls is 3:2, that means 3x+2x=90

Combine like terms: 5x=90

x=18

2x (girls)=36

3x (boys)=54

1/3 of the boys scored full marks, so 54/3=18 boys scored full marks

The number of girls who scored full marks is half of the number who did not score full marks means that 1/3 of the girls scored full marks. 36/3=12, so 12 girls scored full marks.

(I don't know what the question is sorry if it's incorrect but there's not enough information)

Hope this helps!