Multiple choice Which of the following options is the greatest common factor of 64 and 80? 10 14 16 22 Reveal answer Fill a bubble to check yourself C Correct answer Explanation Factors of 64 are 1, 2, 4, 8, 16, 32, 64. Factors of 80 are 1, 2, 4, 5, 8, 10, 16, 20, 40, 80. Greatest common factor is 16.