How do you add fractions with a whole number and a mixed number

Triangle xyz has vertices x(1,3), y(0,0)

If f(x)=3x+1 and f^-1=x-1/3, then f^-1(7)=

Which situation can be modeled by the inequality 5 + 10w ≥ 45? a. you start with $5 and save $10 a week until you have at least $45. b. you start with 5 baseball cards and purchase 10 cards every week until you have at most 45 cards. c. you start with 5 water bottles and purchases cases of 10 water bottles each until you have a total of 45 water bottles. d. you spend $5 plus $10 per week until you have less than $45.