Answer: 8 feet.
Explanation:
Given : The students on a decorating committee create a banner.
Let x be the width of the banner.
The length of the banner is 20 feet.
The length of the banner is 2.5 times its width.
Then, we have
![2.5x=20](https://img.qammunity.org/2019/formulas/mathematics/middle-school/l8bzoeumgmreucuouymlgywz1u27l37tkz.png)
Divide both the sides by 2.5 , we get
![x=(20)/(2.5)=8](https://img.qammunity.org/2019/formulas/mathematics/middle-school/1qorny9lonqrpyn0sm46fe1u8yx4dq4ymo.png)
Therefore, the width (in feet) of the banner= 8 feet.