Can anyone help me? I’ve been stuck all day

Solve for x -2.3(r - 1.2 ) = -9.66 enter you answer as decimal.

Question 10jur's car can travel 340 miles on 12 gallons. jack's car can travel 390 miles on16 gallons. which person has the best mileage (miles per gallon) and what istheir mileage?

Julius sold five times as many computers as sam sold last year. in total, they sold 78 computers. how many computers did julius sell?