It takes 8 high school students, working at identical constant individual rates, 10 hours to paint a certain house. At what time will the house be fully painted if 8 students start painting at 9:00 am and one student, working at the same rate, is added per hour starting at 3:00 pm?
Choose the correct answer:	A) 5:40 pm	B) 5:50 pm	C) 6:00 pm	D) 6:10 pm	E) 6:20 pm
Each student paints at a rate of 1/80 of the house per hour.   In 6 hours, the 8 students can paint 48/80 of the house.   From 3 pm to 4 pm, 9 students paint another 9/80 for a total of 57/80.   From 4 pm to 5 pm, 10 students paint another 10/80 for a total of 67/80.   From 5 pm to 6 pm, 11 students paint another 11/80 for a total of 78/80.   12 students can paint the remaining 2/80 of the house in 2/12 of an hour = 10 minutes.   The house is completed at 6:10 pm.   The answer is 6:10 pm.
<result>D</result>
It takes 8 high school students, working at identical constant individual rates, 10 hours to paint a certain house. At what time will the house be fully painted if 8 students start painting at 9:00 am and one student, working at the same rate, is added per hour starting at 3:00 pm?