9/16 - 5/12 subtract rational numbers

Find the third,fifth and seventh term sequence described by each rule a(n)=n+1

Tamera puts 15/4 gallons of gasoline in her car. which mixed number represents the gallons of gasoline? a) 2 3/4 gallons b) 3 1/4 gallons c) 3 3/4 gallons d) 4 1/2 gallons answer it's worth a lot of points!

Does anyone know how to solve and graph this: 4 + | a + 2 | < 7the only part i don't get is the "4 +"