
To find median $ m $ use formula:
$$ m = \frac{ a + b } { 2 } $$After substituting $a = 17\, \text{cm}$ and $b = 8\, \text{cm}$ we have:
$$ m = \frac{ 17\, \text{cm} + 8\, \text{cm} } { 2 } $$ $$ m = \frac{ 25\, \text{cm} } { 2 } $$ $$ m = \frac{ 25 }{ 2 }\, \text{cm} $$