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?
How many cookies did Sabrina have left after giving 10 cookies to her brother? ** Sabrina had 20 - 10 = <<20-10=10>>10 cookies left after giving 10 cookies to her brother.
How many cookies did Sabrina's mother give her? ** Sabrina's mother gave her 10/2 = <<10/2=5>>5 cookies.
How many cookies did Sabrina have then? ** So, she had 10 + 5 = <<10+5=15>>15 cookies then.
How many cookies did Sabrina give to her sister? ** She gave 15 x 2/3 = <<15*2/3=10>>10 cookies to her sister.
How many cookies are left with her? ** Therefore, she only has 15 - 10 = <<15-10=5>>5 cookies left.
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