Answer:
11
Step-by-step explanation:
11+5=16
16/-16=-1
I think the answer is 3cm I’m not 100% sure
Let's assume
number of shorts is x
we are given
People bought 2 times as many T-shirts as shorts
so, number of T-shirts is 2*x=2x
Dots sells T-shirts ($3) and shorts ($7)
so, total price of T-shirts 
so, total price of shorts 
now, we are given
total sales were $520
so,
total price of T-shirts+total price of shorts = total sales
we will get equation

now, we can solve for x


so,
number of shorts is 40
number of T-shirts is 2*40=80............Answer