150/a=2(90/b) a+3=b
Get a= 15 b= 18.
After the price adjustment, the price of braised pork rice is15+15× 20% =18, and the price of braised pork rice is 18+08× 25% = 22.5.
If we sell C portions of braised pork rice every month, we will sell 500-c portions of braised pork rice.
Profit 18c+22.5 (500 degrees Celsius) -20× 30-0.5× 500 > =3600.
Draw (a conclusion)