So, the question is below, please help me find the answer. :)

For the crisps, for every 3 packets one is free. as you want 6 packets, 2 will be free. so 4 x 1.43 = £5.72

for the fig rolls, if you buy two one will be half price. as we want three, 2 will be normal price and 1 will be half price. 1.08 + 1.08 + 0.54 = £2.70

the total is £2.70+£5.72=£8.42

A) for the n row: 22+(n-1)×6therefore,b) 100-22=78that means (n-1)×6=7878÷6=1313+1=1414th row has 100 seats