Mom give me back my f, ucking xbox or im gonna go to school and tell the teachers you beat me

What is the value of x in the diagram below?

Tomas used 3 1/3 cups of flour and now has 1 2/3cups left. which equation can he use to find f, the number of cups of flour he had to begin with? f+3 1/3=1 2/3 f-3 1/3=1 2/3 3 1/3f=1 2/3 f/3 1/3=1 2/3

Find the nonpermissible replacement for binthis expression. b2/5b +5