Answer
55
Work Step by Step
A $10 \times 10$ matrix $A$ has $\lambda =2$ with multiplicity $4$, then there will be 5 possible Jordan block sizes:
$ 4\\
3,1\\
2,2\\
2,1,1\\
1,1,1,1 $
Then $\lambda =5$ has multiplicity $6$, so there will be 11 possible Jordan block sizes:
$6\\
5,1\\
4,2\\
4,1,1\\
3,3 \\
3,2,1\\
3,1,1,1 \\
2,2,2 \\
2,2,1,1\\
2,1,1,1,1\\
1,1,1,1,1,1$
Hence, the number of Jordan canonical forms is: $5 \times 1 =55$