If 45% of people were voting for Biff + 8% were undecided = 53% were not voting for Marty.
There were 100 – 53 = <<100-53=47>>47% voting for Marty.
If 47% of 200 people were voting for Marty, 0.47 x 200 = <<0.47*200=94>>94 people said they were voting for Marty.
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