Question 1165194
Let x- be the number of notebooks Tim bought in SN Store
y - be the number of notebooks Tim bought in Assorted Store

Tim spent 2.25x in SN Store and 2y in Assorted Store. He spent the same money on both stores therefore 2.25x=2y
There are total of 17 notebooks, therefore x+y=17

We now have two equations
{{{2.25x=2y}}} and
{{{x+y=17}}}

Let y=17-x
{{{2.25x=2y}}}
{{{2.25x=2(17-x)}}}
{{{2.25x=34-2x}}}
{{{4.25x=34}}} 
x=8
y=17-x
y=17-8
y=9

x=8, y=9
He bought 8 in SN store and 9 in Assorted Store

God bless and stay safe.
Hope that helps.
PS: Are you a Filipino? ( Base on currency)