Let's say Sabrina has p number of pencils.
If Justin has 8 more than twice as many pencils as Sabrina, he has 2*p + 8 = 2p+8
Together, Justin and Sabrina has p +(2p+8)=50
This is equal to 3p=50-8
3p=42
The number of pencils that Sabrina has is p=42/3
Sabrina has p=<<14=14>>14 pencils
#### 14