we have to assume a lot of stuff because this problem statement leaves a lot of information unspecified

first, we assume '600' is $600; next we assume that the question is asking what is the total price if a $600 item is sold at 35% off and then there is a sales tax of 7% applied

we leave the answer as succinct as the question

(600 - 600*0.35) + (600 - 600*0.35)*0.07 = 417.3