There is a sales tax of $6 on an item that costs $63 before tax. a second item costs $210 before tax. what is the sales tax on the second item?

The first thing you should do in this case is calculate the tax percentage.
 We then have to apply the following rule of three:
 $ 63 > 100%
 6 $ > x
 Clearing x we have:
 x = (6/63) * (100)
 x = 9.523809524%
 Therefore the taxes of the second item will be
 Tax = (9.523809524 / 100) * 210
 Tax = 20 $
 
 The sales tax on the second item is:
 Tax = 20 $

Ithink the answer is $2.10

I’m having a hard time understanding your question