MATH basic apps

This app is for both who hates math and who loves math, especially for who hates math to learn the basic of math.

The concept is that users "feel" numbers by your calculation about length of number line and angles of triangles several times repeatedly with different numbers.

This math basic app 3stages.
STAGE 1 : Basic add and subtract.
STAGE 2 : Basic of angle and triangle.
STAGE 3 : Basic of inscribed angle and its central angle.

The goal is to learn the relation between inscribed angle and its central angle with proof by calculating a question. Math has over 2000 years history and its power. I would be glad if you find a light of dream or hope by learning basic math questions and answers to apply more difficult questions.