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?
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
#### 119