Please help me with this proof I can not figure this one out

Please help me with this proof, I can not figure this one out.

Let A be an m Times n matrix with rank r. With your group, investigate the relationship between m, n and r. What can you conclude about how r relates to m and n?

Solution

A is a mxn matrix i.e. with m rows and n columns

Rank r is the no of non zero rows of A in a row reduced form

If rank of matrix =r means r can be less than or equal to m.

r<=m

No of independent rows in the matrix = r.