If gas is 4 per gallon and need to drive 23 miles at 17 the how much will it cost?

```

Cost = (Distance / MPG) * Price per gallon

```

Plugging in the given values, we get:

```

Cost = (23 miles / 17 MPG) * $4 per gallon

= 1.35 gallons * $4 per gallon

= $5.40

```

Therefore, it will cost $5.40 to drive 23 miles at 17 MPG when gas is $4 per gallon.