Algebra
posted by Joe .
Ellen is 11 years older than Maja. Last year Ellen was twice as old as Maja. How old is Maja now?

E = M+11
Last year,
(E1) = 2(M1)
so, substitute:
(M+111) = 2(M1)
M+10 = 2M2
M = 12
so, E=23
Check: last year, 22 = 2*11