Answer:
5 hours
Step-by-step explanation:
Scott's delivery rate = 10 pizzas per hour
Kenneth's delivery rate = 12 pizzas per hour
Combined delivery rate
= Scotts delivery rate + Kenneth's delivery rate
= 10 + 12
= 22 pizza's per hour (take reciprocal to find the rate in "hours per pizza")
= 1/22 hours per pizza
Given that they both deliver 110 pizzas combined, the will take
= 1/22 hours per pizza x 110 pizzas
= (1/22) x 110
= 5 hours