Question

Target is having a Back to School sale where all polo shirts are discounted by 20%. Joshua wants to buy five shirts: two cost $10.98 each, one costs $11.50, and two others cost $15.99 each.

Answer 1

By law, sales tax is calculated on the discounted price of the shirts. Would the total cost of the shirts including the 6.5% sales tax be greater if the tax was applied before a 20% discount is taken, rather than after a 20% discount is taken?

Answer:

They will be the same

Explanation:

Sales tax applied before

Total costs before discount = (2*$ 10.98)+$ 11.50+(2*$ 15.99)=$ 65.44

Discount of 20% will be
`\frac {20}{100}* 65.44=$13.088`

New price= 65.44-13.088=$52.352

Adding 6.5% sales tax we obtain
`\frac {6.5}{100}* 52.352=$3.40288`

Total payment= 52.352+3.40288=55.75488

Sales Tax applied after

If 20% is taken after sales tax then the sales tax of 6.5 amounts to

`\frac {6.5}{100}* 65.44=4.2536`

New price= 65.44+4.2536=$ 69.6936

Then 20% discount is
`\frac {20}{100}* 69.6936=13.93872`

Discounted price after sales tax= 69.6936-13.93872

=55.75488

Both systems come to the same value hence there's no difference