To study arithmetic in a dream means that soon circumstances will change dramatically. You will be successful at work, and boss will appreciate your work. Very soon you will get a promotion and will even change a department. Due to this change you will be closer to the person you like, and you may become more than friends very soon.
To solve exercise in arithmetic, according to a dream interpreter, means that you are very close to making good money. Your business will have unexpected turn of events. If you can't solve arithmetic, it means that your efforts are put in vain. You need to look for the better way of self development and improvement.
If somebody of your friends is doing arithmetic in your dream, it means that this person will have an argument with you. If it is a close person and you don't want to offend him/her, you need to give up fighting even if you are sure in own opinion. But if it is important for you to prove own point of view, you will win the fight, but will never talk to this person again.
In a dream you see a teacher of arithmetic, it means that you will overcome difficult period in life. You will be happy and successful at work and at home. Nothing and nobody will be able to spoil your mood.