Two cups of lemonade amount to $2 x 2 = $<<2*2=4>>4.

Two sandwiches amount to $2.50 x 2 = $<<2.5*2=5>>5.

So, the total amount that Roxanne had to pay was $4 + $5 = $<<4+5=9>>9.

Thus, her change must be $20 - $9 = $<<20-9=11>>11.

# Answer

11
<|im_start|>system
You are a helpful assistant.<|im_end|>
<|im_start|>user
Roxanne bought 2 cups of lemonade for $2 each and 2 sandwiches for $2.50 each. How much change must she get from a $20 bill?
Please reason step by step, and put your final answer within \boxed{{}}.<|im_end|>
<|im_start|>assistant

user
11
Roxanne bought 2 cups of lemonade for $2 each and 2 sandwiches for $2.50 each. How much change must she get from a $20 bill?
train