Two sisters, Elizabeth and Margareth, bought beads. Elizabeth bought 1 pack of red and 2 packs of clear beads, while Margareth bought 3 packs of blue and 4 packs of red beads. How many more beads do one sister have than the other, if each pack of beads contains 20 pieces of beads?
Elizabeth bought 1 + 2 = <<1+2=3>>3 packs.
So Elizabeth bought 3 x 20 = <<3*20=60>>60 pieces of beads.
Margareth bought 3 + 4 = <<3+4=7>>7 packs.
So Margareth bought 7 x 20 = <<7*20=140>>140 pieces of beads.
Therefore, Margareth bought 140 - 60 = <<140-60=80>>80 more beads than Elizabeth.
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