Answer:
13 in addition to his first shift, or...
30 without counting his first shift.
Explanation:
He gets paid $23.30 per hour ($396.10/ 17), so divide $699.00 by 23.3 to get how many hours he would need to work in order earn the $699.00. (starting from $0)
if you need to know how many MORE hours he would need to work to get to $699.00 then you do the following
$699.00 - $396.10 = $302.90 (how much more money he needs)
$302.90 / $23.30 = 13 (how many more hours he will need to work after his first shift of 17 hours)