Factorise the expression and divide them as directed.
(5p2 - 25p + 20) (p - 1)
∵ 5p2 - 25p + 20 = 5(p2 - 5p + 4) [∵ 1 × 4 = 4]
= 5[p(p - 1) - 4(p - 1)] [-1 + (-4) = -5]
= 5[(p - 1)(p - 4)]
∴
Thus, (5p2 - 25p + 20) (p - 1) = 5(p-4)