Answer:
The posters cost $52.07.
Step-by-step explanation:
First, you have to calculate the cost of the 20 posters by multiplying the price per poster for the quantity:
$2.89*20=$57.8
Then, you have to calculate the 15% discount by multiplying the cost for 15% and subtracting that amount from the cost:
$57.8*15%=$8.67
$57.8-$8.67=$49.13
Finally, you have to calculate the 6% of $49.13 and add the result to that amount:
$49.13*6%=$2.94
$49.13+$2.94=$52.07
According to this, the answer is that the posters cost $52.07.