20% & DiscountRUs
DiscountRUs offers 40% off while the other offers 1/5 off which is 20% off.
The difference between 40 and 20 is obviously 20.
The factored form for this question is (5x-1)(x-5)
The formula for the nth term is
a1 + (n-1)d where a1 = first term and d = common difference
