小学校ではまず加法と減法を学ぶ。
In elementary school, children first learn addition and subtraction.
加法では、数を足す順序を入れ替えても答えは変わらない。
In addition, changing the order of the numbers does not change the result.
この問題は加法と乗法を組み合わせて解く。
This problem is solved by combining addition and multiplication.