Emilia needs 42 cartons of berries to make a berry cobbler. She already has 2 cartons of strawberries and 7 cartons of blueberries in her cupboard. She decides to go to the supermarket to get more cartons. How many more cartons of berries should Emilia buy?
How many cartons of berries did Emilia have before going to the supermarket? ** She previously had 2 cartons + 7 cartons = <<2+7=9>>9 cartons of berries.
How many cartons of berries does Emilia need to buy? ** Emilia needs to buy 42 cartons - 9 cartons = <<42-9=33>>33 cartons of berries.
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