Answer:
 yard
 yard
Explanation:
Length of string Mrs. Ruiz has = 
 yard
 yard
Mrs. Ruiz needs to hang 3 banners using the string.
Having known that each banner uses same length of string to be hung we can divide total length of sting into 3 equal parts.
So, we can divide 
 yard by 3 as
 yard by 3 as
⇒ 

Changing the division sing to multiplication by taking reciprocal of divisor.
⇒ 

We can now multiply numerators and denominators.
⇒ 
 yard
 yard
∴ Mrs. Ruiz must used 
 yard of string for each banner.
 yard of string for each banner.