The local skating rink pays Mary a fixed rate per pupil plus a base amount to work as a skating instructor. She earns $90 for instructing 15 students on Monday afternoon. Last Friday, she earned $62 for working with 8 students. Lisa is also a skating instructor. She receives half the base amount that Mary does, but she is paid twice as much per student. Who would earn more money instructing a class of 20 students?

lisa would earn more money

Step-by-step explanation:

let say mary base price = x

mary per student price = y

x+15y = 90

x+8y = 62

7y = 28

y =4

x = 30

mary  will earn for 20 students = 30 + 20*4 = 110

lisa base money = 30/2= 15

lisa per student = 4*2=8

lisa earning for 20 students

= 15 + 20*8 = 175

lisa will earn more money

step-by-step explanation:

      2

  2 is to go somewhat to the top right of a because it is squared    

v= a h/3