Which value of a would make the expression 5 1/3÷4/a equivalent to a whole number?

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?

Which one is true about the hexagons ?

Two times a number plus three times another number equals 4. three times the first number plus four times the other number is 7. find the numbers