There will be 18 members and she wants to allow 2 biscuits per member so that’s 18*2 = <<18*2=36>>36 biscuits
Her biscuit recipe yields 9 biscuits and she needs to make 36 biscuits so she needs to make 36/9 = <<36/9=4>>4 batches of biscuits
1 batch of biscuits uses 1 1/4 cup flour and she needs to make 4 batches so she will use 1.25*4 = <<1.25*4=5>>5 cups of flour
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