Does this man need clothes?

Evaluate the expression for the given value of the variable 7a - 4a for a =8

Janie has $3. she earns $1.20 for each chore she does and can do fractions of chores. she wants to earn enough money to buy a cd for $13.50. write an inequality to determine the number of chores, c, janie could do to have enough money to buy the cd.

If g^-1(x) is the inverse of g (x) which statement must be true