<PRE><B>Question 821523</B>
let x be the number of seats in theater 3, then
2x is the number of seats in theater 1 and
x+150 is the number of seats in theater 2
now we can write
2x +(x+150) +x = 802
combine x terms
4x +150 = 802
subtract 150 from both sides of =
4x = 652
divide both sides of = by 4
x = 163
theater 1 has 2*163 seats = 326 seats
theater 2 has 163+150 seats = 313 seats
theater 3 has 163 seats
check our answers
326 + 313 + 163 = 802
802 = 802 
answers check   :-)
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