Answer:
[tex]total = 48[/tex]
Step-by-step explanation:
[tex] \frac{red}{blue} = \frac{3}{5} [/tex]
From this you conclude, assuming that the only types of pen colors are red and blue:
[tex] \frac{red}{total} = \frac{3}{3 + 5} [/tex]
[tex] \frac{18}{total} = \frac{3}{8} [/tex]
