It is: 2*2*71 = 284
by using a prime factor tree
Use a factor tree.
50 25,2 5,5,2
90 45,2 15,3,2 5,3,3,2
29x3 both prime so your done
A factor tree shows the prime factors of the working number and can also be used as a visual demonstration to show the prime factors of the working number.
The tree method is a diagram that does not display properly in this answer area.
21
10 2 x 5
220 110,2 55,2,2 11,5,2,2
The factor tree would be hard to show so here is the prime factorization.41 times 5
103 is prime, so it's only factors are 1,103