Addition with ones and tens

Question

The children on the planet Veeton count in Zips and Zaps.

If the sum is correct how many Zaps make a Zip?

\begin{array}{ccc} & \text{Zips} & \text{Zaps} \\ & 3 & 8 \\ +& 2 & 4 \\ \hline & 6 & 3 \end{array}

Answer 1

If $b$ is how many zaps make a zip, the addition is $$ (3b+8)+(2b+4)=\dots $$ Can you finish?

Answer 2

Hint:

They're telling you that 12 zaps and 5 zips is the same as 3 zaps and 6 zips.