Answer:

Step-by-step explanation:
Let total x black and y brown shoes are sold in a week
So total number of shoes sold in a week is = x+y
It is given that
of all shoes sold are black
So 

So the number of brown shoes sold in a week in terms of black shoes are x/2
It would be: 87/120 * 100 = 72.5
Percentage decrease = 100 - 22.5 = 27.5
So, your final answer is 27.5%
Hope this helps!
Answer:
y=(x-4)^2+0
Step-by-step explanation:
Answer: 3.6
Step-by-step explanation: 3x1.2= 3.6