← mixed practice i cards you don't know will reappear later

you should create an account to save your progress. it only takes a minute!
new card

what is the smallest positive integer that is not a factor of (20!)?

click to see back →
new card

since (20!) is the product of the integers from 1 to 20, all twenty of those numbers will be factors. since the product contains 3*7, 21 must be a factor. since the product contains 2*11, 22 must be a factor. the first integer that is not a positive factor is the prime number 23.

i knew this card i didn't know this card
you have mastered 0 out of 36 cards
you are reviewing 0 out of 36 cards
you are learning 0 out of 36 cards

have feedback about this card? please email help@www.catharsisit.com