Question

【数学】商场出售的某种商品,每件进价为20元,售价为40元.

Answer 1

设降价率是x

∴40(1-x)²=32.4

(1-x)²=0.81

∴x=0.1或x=1.9 舍去

y=(500+10x/0.2)×(40-x-20)

=(500+50x)(20-x)

=50(10+x)(20-x)

=50(-x²+10x+200)

=-50(x²-10x+25)+50×225

=-50(x-5)²+11250

当降价5元时可获最大利润11250元