I am a little confused. I have been told that electrons carry a charge of $-1.6 \cdot 10^{-19}$ coulombs, and that 1 coulomb is $6.25 \cdot 10^{18}$ electrons, and $1 \,\mathrm{A}$ is the current from when $1$ coulomb of charge flows in $1$ second.
However, when we are asked questions such as 'How many electrons pass a point when a current of $0.4\,\mathrm A$ flows for $900$ seconds?'
I understand $Q = I \cdot t = 0.4 \cdot 900 = 360\,\mathrm C$ and
$$\text{no. of electrons} = \dfrac{\text{total charge}}{\text{charge of one electron}}$$
so
$$\text{no. of electrons} = \frac{360}{-1.6 \cdot 10^{-19}} = -2.25 \cdot 1021 $$
So do I just give my answer as a negative number of electrons? Or do I just totally ignore the negative sign?