First find out how much he makes in 8 hours (9x8=72). Then subtract 72 from 155 (155-72=83). Then divide 83 by 6 (83/6=13.8333). Since 83 is not evenly divisible by 6, and since he can't deliver .8333 of a delivery, we would round up, giving us 14). Ben would need to make 14 deliveries in 8 hours to make more than $155 :) Hope this helps you :)
The distance is 18 units and the equation would be (-8 - 10)
6+4• (5-7)^2
(5-7)^2
-2^2
4
6+4+4
=14
25 pens is better because if you see the cost of one it will be cheaper
