问数学寂静的一道题目，感谢

nokidding

各位狗友，大谢了。
一个制作BOWL的工厂，每个BOWL售价12刀，gross profit的计算式-2（x-5）^2+10(单位：千），x是BOWL量的千位数，问生产3000个比生产4000个BOWL每个贵多少？
A0.33
B0.67
C1.33
D1.67
感谢，是哪个啊

UMHIVTDC

我認為是C

Gross Profit for 3000 Bowls = -2(3-5)^2 + 10 = 2 => $2000
Gross Profit for 4000 Bowls = -2(4-5)^2 + 10 = 8 => $8000

Cost for 3000 Bowls = Sale - Gross Profit = (12*3000) - 2000 => Each Bowl = [36000 - 2000]/3000 =11.33
Cost for 4000 Bowls = Sale - Gross Profit = (12*4000) - 8000 => Each Bowl = [48000 - 8000]/4000 = 10

11.33 - 10 = 1.3

nokidding

感谢。