On rainy mornings, Mo drinks exactly N cups of hot chocolate (assume that N is an integer). On mornings that are not rainy, Mo drinks exactly 5 cups of tea. Last week Mo drank a total of 22 cups of tea and hot chocolate together. If during that week Mo drank 8 more tea cups than hot chocolate cups, then how many rainy days were there last week?  Select the correct option.
A) 2
B) 4
C) 3
D) 5
E) 6

Rationale: "t = the number of cups of tea c = the number of cups of hot chocolate t + c = 22 t - c = 8 - > t = 15 . c = 7 . mo drinks 5 cups of tea a day then number of days that are not rainy = 15 / 5 = 3 so number of rainy days = 7 - 3 = 4 b is the answer ."
Answer: B