Megan was the lead actress in 100 * 80% = <<100*80*.01=80>>80 plays.

So Megan was not the lead actress in 100 - 80 = <<100-80=20>>20 plays.

# Answer

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<|im_start|>system
You are a helpful assistant.<|im_end|>
<|im_start|>user
Megan is an actress. She was the lead actress in 80% of her work. In total, Megan participated in 100 plays. How many times Megan was not the lead actress?
Please reason step by step, and put your final answer within \boxed{{}}.<|im_end|>
<|im_start|>assistant

user
20
Megan is an actress. She was the lead actress in 80% of her work. In total, Megan participated in 100 plays. How many times Megan was not the lead actress?
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