What’s the answer and work for this? Please someone tell me

Whats The Answer And Work For This Please Someone Tell Me class=

Answer :

Answer:11 hours

Step-by-step explanation:

you would add all three hours and then divide by 3 but first you would have to convert the minutes into hours so it would be 900/60 which is 15 so then you would do 8+10+15 / 3 which gives you 11