Human: 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? Assistant:
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.