Answer:
$6; $7
Step-by-step explanation:
Since they both had 9 dozen oatmeal cookies, we can do 111-75 to see that the difference in money spent is 36.
Then divide that by 6 to see that each dozen of chocolate is $6.
Now we take 111-48 to get 63. We get the 48 from how much the first customer spent on chocolate cookies.
Divide 63 by 9 since thats how many dozens of oatmeal cookies were bought and you get $7.
Hope this helps