In hypothesis testing, the level of significance, denoted as \( \alpha \), represents the probability of rejecting the null hypothesis when it is true. In this case, since you are testing at the 5% level of significance, the value of \( \alpha \) is:
\[ \alpha = 0.05 \]
This means that there is a 5% risk of concluding that the true mean withdrawal is greater than R240 when, in fact, it is not.