Abackpack that normally sells for $39 is on sale for 33% off. find the amount of the discount and the sale price.

1. 33% = 0.33 
$39 x 0.33 = $12.87 
$39 - $12.87 = $26.13 

Discount: $12.87 
Sale price: $26.13 

First find 10%
10% of $39 = $3.90
so...
30% of $39 = $11.70
This is because 30% is 10% multiplied by 3. So you just have to multiply 3.90 by 3.
Then you would work out 1%
1% of $39 = $0.39
so...
3% of $39 = $1.17
This follows the same principle as before.
Now you have to add them together to get the discount price.
11.70 + 1.17 = $12.87

To get the price after the discount, simply take the discount price away from the usual price:
39 - 12.87 = $26.13

Therefore the two answers to your questions are..
$12.87
and..
$26.13
Hope this helped :)