First, Stephanie needs to figure out how many cups of soy sauce she needs total, 2 cups + 1 cup + 3 cups = <<2+1+3=6>>6 cups total of lower sodium soy sauce.
Then Stephanie needs to figure out how many ounces are in 6 cups of lower sodium soy sauce, 6 x 8 ounces each cup = <<6*8=48>>48 total ounces of lower sodium soy sauce.
Next Stephanie needs to figure out how many bottles of soy sauce to purchase to get 48 ounces, where 1 bottle has 16 ounces, 48 / 16 = <<48/16=3>>3 bottles of lower sodium soy sauce.
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