My Boyfriend's Brother Is My Fated Mate.

Evan Miller, a modern young man, accidentally travels to a bizarre cultivation world where math is the core of power.Magical tools are abacuses, rulers, and compasses; cultivation techniques are arithmetic formulas; and combat strength is determined by one's mathematical ability. Just as a sect is recruiting disciples, Evan easily solves the math entrance exam. With his mathematical knowledge far surpassing that of this world, he crushes everyone in the sect tournament and rises directly to become Elder Miller. Then, the sect leader recommends him to compete in the Tournament of the Five Great Sects.