Respuesta :
Answer:
10%
Step-by-step explanation:
i used cross multiplication.
100%=$20
????=$18
100•18/20
=90
this is its percentage. to find the percentage decrease take 100-90
=10
%10 of 20 is 2, so take 2 off 20 you get 18
%2 of 20 is .4, so take .4 off 20 you get 19.60
%11 of 20 is 2.2, so take 2.2 off 20 you get 17.80
%18 of 20 is 3.6, so take 3.6 off 20 you get 16.4
B is the correct answer
%2 of 20 is .4, so take .4 off 20 you get 19.60
%11 of 20 is 2.2, so take 2.2 off 20 you get 17.80
%18 of 20 is 3.6, so take 3.6 off 20 you get 16.4
B is the correct answer