(140) = 2 * (70)
(70) = 2 * (35)
(35) = 5 * 7
Prime factors of 140: 2,2,5 and 7
140 70,2 35,2,2 7,5,2,2
The factor tree is as follows: 114 57,2 19,3,2
119 7,17
Since 61 is already prime, a factor tree is not necessary. The prime factorization of 51 is 3 x 17, which wouldn't make much of a tree. More like a factor shrub.
Yes - 7 is a factor of 140 because 7 x 20 = 140.
140 70,2 35,2,2 7,5,2,2
140 70,2 35,2,2 7,5,2,2
70,2 35,2,2 7,5,2,2
98 49,2 7,7,2 140 70,2 35,2,2 7,5,2,2
140 2, 70 2, 2, 35 2, 2, 5, 7
Use a factor tree. 98 49.2 7,7,2 140 70,2 35,2,2 7,5,2,2
140 70,2 35,2,2 7,5,2,2 2 x 2 x 5 x 7
no
The factor tree is as follows: 114 57,2 19,3,2
No.
yes
991 is already prime. No tree is required.