The total number of packages is 3 + 10 + 8 = <<3+10+8=21>>21.

Julia bought 21 × 19 = <<21*19=399>>399 balls.

# Answer

399
<|im_start|>system
You are a helpful assistant.<|im_end|>
<|im_start|>user
Julia bought 3 packs of red balls, 10 packs of yellow balls, and 8 packs of green balls. There were 19 balls in each package. How many balls did Julie buy in all?
Please reason step by step, and put your final answer within \boxed{{}}.<|im_end|>
<|im_start|>assistant

user
399
Julia bought 3 packs of red balls, 10 packs of yellow balls, and 8 packs of green balls. There were 19 balls in each package. How many balls did Julie buy in all?
train