math
posted by kevin .
Brian O'Reilly earns twice as much each week as a tutor than he does pumping gas. His total weekly wages are $150 more than that of his younger sister. She earns one quarter as much as Brian does as a tutor. How much does Brian earn as a tutor?

i think its 37.50

let his wages from pumping gas be x
then his wages from tutoring is 2x
Brian's total wages = 3x
Sisters wages are 1/4 of Brian's tutor wages
= (1/4)(2x) = x/2
His wages from tutoring are 150 more than sister's wages
3x = x/2 + 150
6x = x + 300
5x = 300
x = 60
So he makes 2x or $120 as a tutor.
check: Brian's wages = 60 + 120 = 180
Sister's wages = (1/4) of 120 = 30
180 is 150 more than 30 
this problem is killing me