The two numbers are x and y; therefore we can suggest this system of equations:
x+y=150
x/y=3/2
We can solve this system of equations by substitution method.
x/y=3/2 ⇒x=3y/2
(3y/2)+y=150
3y/2 + y=150
lowest common multiple=2
3y+2y=300
5y=300
y=300/5
y=60
x=3y/2
x=(3*60)/2=180/2=90
Answer: the bigger number is 90