问题 解答题

某电视机厂计划在下一个生产周期内生产两种型号电视机,每台A型或B型电视机所得利润分别为6和4个单位,而生产一台A型或B型电视机所耗原料分别为2和3个单位;所需工时分别为4和2个单位,如果允许使用的原料为100单位,工时为120单位,且A或B型电视和产量分别不低于5台和10台,应当生产每种类型电视机多少台,才能使利润最大?

答案

设生产A型电视机x台,B型电视机y台,则根据已知条件线性约束条件为

2x+3y≤100
4x+2y≤120
x≥5
y≥10
,即
2x+3y≤100
2x+y≤60
x≥5
y≥10

线性目标函数为z=6x+4y.

根据约束条件作出可行域如图所示,作3x+2y=0.

当直线l0平移至过点A时,z取最大值,

解方程组

2x+3y=100
2x+y=60
x=20
y=20

生产两种类型电视机各20台,所获利润最大.

完形填空
完形填空。
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