9/10 times a number plus 6 is 51 what is the answer ?

I believe the answer is 50 since 9/10*50= 45, then 45+6=51.

The answer is c because you turn 17.5% into a decimal which gives you .175 then you times that by $361.35 which gives you 63.23625 but then you round that which gives you 63.24. then you at 63.24 pulse 361.35 and you round it which gives you $425