Question 1128629
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<pre>
2*120 + 150*(n-2) = 180*(n-2)


240 = 180*(n-2) - 150*(n-2)


240 = 30*(n-2)   ====>  n-2 = {{{240/30}}} = 8   ====>  n = 8+2 = 10.   <U>Answer</U>.
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Solved.