And there was an AP

A finite arithmetic progression of n terms have this properties:

${ a }_{ 2 }+{ a }_{ 11 }= 78$

${ a }_{ 4 }+{ a }_{ 8 }= 72$

$\sum _{ k=1 }^{ n }{ { a }_{ k } } =468$

Find the common difference and the number of terms.