Anna needs 3 x 50 = <<3*50=150>>150 slices of ham to make 50 sandwiches.

Anna needs 150 - 31 = <<150-31=119>>119 more slices of ham

# Answer

119
<|im_start|>system
You are a helpful assistant.<|im_end|>
<|im_start|>user
Anna puts three slices of ham in each sandwich. If she has 31 slices of ham, how many more slices of ham does she need to make 50 ham sandwiches?
Please reason step by step, and put your final answer within \boxed{{}}.<|im_end|>
<|im_start|>assistant

user
119
Anna puts three slices of ham in each sandwich. If she has 31 slices of ham, how many more slices of ham does she need to make 50 ham sandwiches?
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