Lizzy: Katrina has 120 cookies to sell at her bakery. She plans to take home any cookies she doesn’t sell by the end of the day. In the morning, she sells 3 dozen cookies. During the lunch rush, she sells 57 cookies. In the afternoon, she sells 16 more cookies. How many cookies does she have left to take home?.
Me: Hmmm, let me think. I think this is the detailed solution:
There are 12 cookies in 1 dozen, so in the morning, she sold 12 x 3 dozen = 36 cookies. Throughout the day, she sold 36 cookies in the morning + 57 cookies at lunch + 16 cookies in the afternoon = 109 cookies. She started with 120 cookies – 109 cookies sold = 11 cookies to take home. Final answer: 11.