can any one tell me a way of working out a percentage from a total for tax purposes.

Example; if i have a total of 78 and the tax was 17.5% it would be
78 divide 47 x 7 =11.61

can anyone tell me how to work it out if the tax was 16%
thanks

"78 divide 47 x 7 =11.61 " ??????
I have no idea where you are getting that from.

17.5% of 78 = .175 x 78 = 13.65
16% of 78 = .16 x 78 = 12.48

To calculate the tax amount from a total for tax purposes, you can use the following formula:

Tax amount = Total amount x (Tax percentage / 100)

For example, if you have a total of 78 and the tax rate is 17.5%, you can calculate the tax amount as follows:

Tax amount = 78 x (17.5 / 100) = 13.65

Similarly, if the tax rate is 16%, you can calculate the tax amount as follows:

Tax amount = 78 x (16 / 100) = 12.48

So, the tax amount for a total of 78 with a 16% tax rate would be 12.48.