Question 881049
perimeter = (l+w)*2
area = w*l

Out of this we learn that you want to look for 2 divisors that counted together are as low as possible
all divisors of 30 :
1*30 , 2*15 , 3*10, 5*6, 6*5, 
5*6 is the answer because 5+6 = only 11

so perimeter = 11*2 = 22