Write the prime factorization of the numerator and denominator. Then write the fraction in lowest terms. 315/1575

315 / 1575 = (3 2 * 5 * 7) / (3 2 * 5 2 * 7) = ((3 2 * 5 * 7) : (3 2 * 5 * 7)) / ((3 2 * 5 2 * 7) ... 315) / (1575 : 315) = 1 / 5 Divide fraction's both numerator and denominator by ... prime factors, by the lowestpowers. gcf, gcd (315; 1575) = 3 2 * 5 * 7 = 315;