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8/40

5
8[40
40
------
00

Is this the right way I did it

Looks like you got it upside down - rather than finding 8/40 you found 40/8. 8 divided by 40 is 1/5, or 0.2:



\begin {matrix}
& \underline {0.2} \\
40 \ |& 8.0 \\
& \underline{8.0} \\
& 0
\end{matrix}