(xy=x times y just fyi)
bought bike for 368.9
this was including sales tax of 8.5%
(percent means part out of 100 so 8.5%=8.5/100=0.85/10= 0.085/1 1=0.085)
so paid=price+tax
paid=368.9
price=p
tax=p times 8.5%=0.085
368.9=p+p times 0.085
368.9=p+0.085p
or
p+0.085p=368.9
the answer is C