If 15 litres is for 50km, what is the distance for 18 litres

Ivan and jeff buy a package of 8 pens for $4.00. ivan wants 5 of the pens, and jeff wants 3.how much should each student pay?

The estimated number of people to attend the last bengals game of the season was 2000. the actual number of fans attending was 1200. by what percent did the estimate differ from the actual?

What are the solutions of the system? solve by graphing. y = -x^2 - 3x + 2 y = -2x + 2