There are a few reasons thay Tammy's
sample may not be valid. Firstly, she had a
relatively small sample size, meaning that
she had a potentially large margin of error.
Additionally, she was asking students from
her math class, which could also have
created a bias simply due to the fact that
they were currently doing math. In order to
survey a more valid sample, she should
consider student of other grade levels and
from other classes to ensure that she has
the most information possible and to create
variation in her sample.
