Question 1049491
I'll take a guess:
The combined width of the pictures is:
{{{ 5*5 = 25 }}} in
There are {{{ 6 }}} equal spaces when you
count the ones on both sides of the {{{ 5 }}}
pictures
{{{ 37 - 25 = 12 }}} inches available for spaces
{{{ 12/6 = 2 }}} inches 
the is 2 inches around each picture
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hope I got it