Answer:
6
Step-by-step explanation:
Number of water bottles bought by Sylvia = 24
Number of water bottles sold by Sylvia = [tex]x[/tex]
Number of water bottles left with Sylvia = [tex]24-x[/tex]
Number of water bottles bought by Sam = 36
Number of water bottles sold by Sam = Three times as many as bottles as Sylvia sold = [tex]3x[/tex]
Number of water bottles left with Sam = [tex]36-3x[/tex]
It is given that the number of water bottles left with Sylvia and Sam are equal.
i.e.
[tex]24-x=36-3x\\\Rightarrow 2x=12\\\Rightarrow x =\bold{6}[/tex]
So, number of water bottles sold by Sylvia = 6