To find a sales tax of 6% on a purchase of $90.00 using the proportion method you would write the following:

6/100 = ST/$90

The calculations in this problem would give you the following: (ST)= $540.00

100 ST = 540

Divide 540 by 100.

The answer would be $95.40 because 6/100 is .06, which equals 540/90 = 6% and you multiply that by 90. What you get is 5.4, and add that to 90, you get $95.40.

The problem just asks for the tax, not the total purchase.

Ok then, it'd be $5.40...

You have made a purchase of $87.00. The state sales tax is 6% and the county tax is 1.25%. The total tax is _____ .

You have made a purchase of $87.00. The state sales tax is 6% and the county tax is 1.25%. The total tax is _____ .

To find the sales tax of 6% on a purchase of $90.00 using the proportion method, you would set up a proportion where the tax rate is compared to the purchase amount. The proportion is written as:

6/100 = ST/$90

To solve for the sales tax (ST), you cross-multiply and solve for ST:

(6 * $90) / 100 = ST

Combining and simplifying the numbers:

$540 / 100 = ST

Which gives you:

ST = $5.40

Therefore, the sales tax on a purchase of $90.00 with a 6% tax rate would be $5.40.