Answer: A) 
B) 75%
C) She bought 1.5 dozen of plain bagels and 0.5 dozen of sesame bagels.
Step-by-step explanation:
Given: The ratio of the number of sesame bagels to the number of plain bagels is 1:3.
Let the number of sesame bagels be x and the number of plain bagels be 3x.
Then total bagels=x+3x=4x
A) The fraction of bagels are plain
B) The percent of bagels are plain
C) If ill bought 2 dozen bagels, the number of plain bagels![=\frac{3}{4]\times2=\frac{3}{2}\text{ dozen}=1.5\text{dozen}](https://tex.z-dn.net/?f=%3D%5Cfrac%7B3%7D%7B4%5D%5Ctimes2%3D%5Cfrac%7B3%7D%7B2%7D%5Ctext%7B%20dozen%7D%3D1.5%5Ctext%7Bdozen%7D)
The number of sesame bagels 
Hence, she bought 1.5 dozen of plain bagels and 0.5 dozen of sesame bagels.