There were 80/2 = <<80/2=40>>40 wireless mice sold.

There were 80/4 = <<80/4=20>>20 optical mice sold.

So, there were a total of 40 + 20 = <<40+20=60>>60 wireless and optical mice sold.

Therefore, 80 - 60 = <<80-60=20>>20 trackball mice were sold this month.

# Answer

20
<|im_start|>system
You are a helpful assistant.<|im_end|>
<|im_start|>user
Marky owns a computer accessory shop. For this month, half of their sales are wireless mice, one-fourth are optical mice, and the rest are trackball mice. If Marky's shop was able to sell a total of 80 mice, how many of them are trackball mice?
Please reason step by step, and put your final answer within \boxed{{}}.<|im_end|>
<|im_start|>assistant

user
20
Marky owns a computer accessory shop. For this month, half of their sales are wireless mice, one-fourth are optical mice, and the rest are trackball mice. If Marky's shop was able to sell a total of 80 mice, how many of them are trackball mice?
train