Answer :
exp.
100 $;
discount of 20% => 80$;
discount of 12%% => 80 - 80*(12/100) = 71.4 $;
100 - (x/100)*100 = 71.4 => x = 29.6 => a single discount of 29.6%;
100 $;
discount of 20% => 80$;
discount of 12%% => 80 - 80*(12/100) = 71.4 $;
100 - (x/100)*100 = 71.4 => x = 29.6 => a single discount of 29.6%;
