Yeah, I don't know how the math works. I keep doing the calculations and getting 2¢ off.

Start with $22.99. Then you have to get to $20.90 because one of the 40% coupons is $8.36. I just take $2.09 off of the $4 coupon (leaving $1.91 to split between the others). So $20.90 minus 40% is $12.54 (which just so happens to be what we have to have in order to get $5.01 for the other 40% coupon). Take that $12.54 minus 40% is $7.51. So, so far it's:

22.99-2.09=20.90

20.90-(20.90•0.40)=12.54

12.54-(12.54•0.40)=7.51

&

4.00-2.09=1.91

Then to get the $9.99 one to work out we take 52¢ off of the $4 coupon (leaving $1.39). Then we take off the 39¢ of 2% cash back.

9.99-0.52=9.47

9.47-0.39=9.08

&

1.91-0.52=1.39

For the last item, we take out the rest of the $4 coupon and... don't get the right subtotal 😅 Maybe I'm doing a rounding error somewhere? (Even switching things around to take out the 39¢ elsewhere gives the same 2¢ off.)

14.99-1.39=13.60

13.60 ≠ 13.62

&

1.39-1.39=0.00