The factors of a number are given below:
1,2,4,5,8,10,16, 20, 40, 80
what is the number?

Find the number of positive three-digit even integers whose digits are among 9, 8, 7,5, 3, and 1.

Will used 20 colored tiles to make a design in art class. 5/20 of his tiles were red. what is an equivalent fraction for the red tiles?

Pls! does anybody know a shortcut for answering these types of questions in the future?