When P=MR=MC, equilibrium is reached.

mc=0.3q^2-4q+ 15=55 3q^2-40q-400=0 q = 20

Stop production condition p = Mr = MC = 0.3q2-4q+15 = AVC = 0.1q2-2q+15.

That is P=0.3Q2-4Q+ 15.

0.3q2-4q+ 15=0. 1q^2-2q+ 15

Q= 10 P= 5 when solving equations.

P=5 is the stopping point, not less than 5.

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