the answer is $350.46
steps:
the original price is $620
so first you were discounted 30% so :
620*30%=186 ( this tells you how much money was taken off after the 30% discount)
then you subtract that from the original amount ( 620-186= 434)
now your new amount is $434 so your next discounted amount was 15% repeat the same process: 434*15%=65.1 then (434-65.1=368.9)
finally, you multiply 368.9 with 5% ( 368.9 *5%= 18.445)
--> continue as you did before ( 368.9-18.445=350.455) round it to nearest cent you get your final answer 350.46