Q: Sabrina gave 10 cookies to her brother. Her mother gave Sabrina half the number of cookies she gave her brother. Then Sabrina gave two-thirds of her cookies to her sister. If Sabrina had 20 cookies at the start, how many cookies are left with her?
A: Sabrina had 20 - 10 = 10 cookies left after giving 10 cookies to her brother. Sabrina's mother gave her 10 / 2 = 5 cookies. So, she had 10 + 5 = 15 cookies then. She gave 15 x 2 / 3 = 10 cookies to her sister. Therefore, she only has 15 - 10 = 5 cookies left. The answer is 5.

Q: Emily can type 60 words per minute. How many hours does it take her to write 10,800 words?
A: In an hour, Emily can type 60 words * 60 minutes = 3600 words. It will take her 10800 / 3600 = 3 hours to write 10800 words. The answer is 3.

Q: Wendy is a fruit vendor, and she sells an apple at $1.50 each and one orange at $1. In the morning, she was able to sell an average of 40 apples and 30 oranges. In the afternoon, she was able to sell 50 apples and 40 oranges. How much are her total sales for the day?
A:
There were an average of 40 + 50 = 90 apples. And, there were 30 + 40 = 70 oranges. Thus, Wendy gained 90 x $1.50 = $135 for selling apples. And, she gained an additional 70 x $1 = $70 for selling oranges. Therefore, her total sales for the day is $135 + 70 = $205. The answer is 205.