Answer:
[tex]\frac{2}{5}[/tex]
Step-by-step explanation:
These individual slices are equal size, so they have an equal chance of being landed on.
There are 4 white slices out of the 10 total slices.
This means there's a [tex]\frac{4}{10}[/tex] chance Lena will land on white.
[tex]\frac{4}{10}[/tex] simplified is [tex]\frac{2}{5}[/tex].
