I am doing masters in computer science in US, but I havent been used to solving math problems nicely. I come from not so well undergrad or schooling. I also did not undserstand the importance of it earlier. But even easy modulus sums am not able to do in my online assesments. That idea is not striking for me because I havent been exposed that much. I prepared GRE so hard and still scored only 155 in Math. What are some advices that I can get ? I did my undergrad in computer engineering should I switch my masters now which is not very easy.