The average of 12 numbers is 47. The average of the first 5 numbers is 45 and the average of the next 4 numbers is 52. If the 10th number is 10 less than the 11th number and is 5 more than the 12th number, then what is the average value of the 11th and 12th numbers?
1
44.5
2
42.5
3
46.5
4
47.5