Answer :
Given:
The initial speed of the motorcycle is,
[tex]u=25\text{ m/s}[/tex]The acceleration is,
[tex]a=6\text{ m/s/s}[/tex]The time interval is,
[tex]t=6\text{ s}[/tex]The final speed is given by,
[tex]v=u+at[/tex]Substituting the values we get,
[tex]\begin{gathered} v=25+(6\times6) \\ =61\text{ m/s} \end{gathered}[/tex]Hence, the final speed is 61 m/s.