ratios suck

So I just did a math problem and it asked me if a=d(1/2) what is the ratio of a to d? And idk if it's 1/1/2 1:1/2 or 2/1 2:1 or 1/2 1:2. I say it's either 1/1/2 1:1/2 which is the same thing as 2/1 2:1 cause 1*2=2 and 1/2*2=1.

Idk I got into an argument with my parents cause of that so I have to talk to my math teacher cause he says its 1/2 but i don't see how that's correct.

Anyways I'm just getting to bed and tomorrow will be the first day at school with my new hair so hopefully all the reactions are good ones. I will update on the reactions tomorrow. I'm gonna actually do my makeup tomorrow so hopefully that intensifies my hair and makes people's reaction better