a computer in Texas cost $420 and the tax is $60 what is the tax rate? can anyone explain how I get the answer

If I'm interpreting this question correctly, then you want to know the tax per dollar. In order to find that, you need to find the percentage of $420 that equals $60. So,

420x = 60

x = 60/420

x = 0.1429 (rounded)

So, the tax rate would be this value multiplied by 100%.

0.1429 x 100% = 14.29%