irreducible fraction; fraction in lowest terms
Mathematical term for a fraction whose numerator and denominator are coprime (i.e., cannot be simplified further).
Two-thirds is an irreducible fraction, but four-sixths is not.
分数を既約分数に直すには、分子と分母を最大公約数で割ります。
To reduce a fraction to its lowest terms, divide the numerator and denominator by their greatest common divisor.