Question 262771
Hello, 
We can set up 2 equations like this: Let x represent the members and y be the non-members.
x+y=150
25x+35y=4200
Now, let's multiply the first equation by -25 to give us:
-25x-25y=-3750 Add this to the second equation:
25x+35y=4200 And we get:
10y=450 Divide each side by 10 to get:
y=45 
There we go! 
We now know there were 45 non-members. Plug this into either original equation to find the number of members. 
I'll let you figure this part.
Make sense?
RJ
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