Put the number you want to factor at the top. Each successive "branch" breaks the number into factors, then factors of factors. When all the factors are prime, the tree is complete.
Example: 210
210 Divide by two.
105,2 Divide by three.
35,3,2 Divide by five.
7,5,3,2 Stop.
2 x 3 x 5 x 7 = 210
IT IS PRIME there is no factor tree
The factor tree of 50:5025,25,5,25025,25,5,2
21
The factor tree for 148: 148 74,2 37,2,2
Factor tree for 49:49/ \7 x 7497,7
factor tree of 216
IT IS PRIME there is no factor tree
Factor tree of 204
The factor tree of 50:5025,25,5,25025,25,5,2
21
83 is prime. No tree.
The prime factor tree of 280 is:140,270,2,235,2,2,27,5,2,2,2
Factor Tree of 20: ........20 ......../ \ .......4 5 ....../ \ .....2 2
A tree.
The factor tree for 148: 148 74,2 37,2,2
311 is prime. It doesn't need a factor tree.
NEVER! A factor tree is strictly division. Factors at the end of a factor tree should all be whole numbers.