Start by finding the total that is left, $1700 car price - $500 earned at car wash = $<<1700-500=1200>>1200 remaining.
So the six friends should pay $1200 / 6 people = $<<1200/6=200>>200 each.
Since Brad is not joining, then the 5 friends have to split Brad's share which is $200/5 = $<<200/5=40>>40 each.
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