Out of every 5 berries, she eats 1, so only 5 strawberries - 1 strawberry = <<5-1=4>>4 strawberries go into the basket for each handful.
The basket holds 60 strawberries, so it will take 60 strawberries / 4 strawberries per handful = <<60/4=15>>15 handfuls to fill the basket.
So in total, Susan will pick 60 strawberries + 15 handfuls * 1 strawberry eaten per handful = <<60+15*1=75>>75 strawberries.
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