Answer:
Brittany is sharing number of 
 s with her sister = 6
s with her sister = 6
Explanation:
Let the shell collection of Brittany = x
She is giving 
 of her shell collection to her sister.
 of her shell collection to her sister.
Therefore, shells received by her sister = 

 th of her shell collection =
th of her shell collection = 

Number of 
 s her sister received =
s her sister received = 

 = 

 = 

 = 6
Therefore, number of 
 received by her sister = 6
 received by her sister = 6