由題意得
1.5x×0.9-x>45,①
1.5x×0.9-x-
60 |
a |
x≤200,③
1.5x×0.9×a≥1000,④
由①③得129<x≤200,⑤
當a=1時,解②得x=
2700 |
7 |
當a=2時,解②得x=
1500 |
7 |
當a=3時,解②得x=
1300 |
7 |
當a=4時,解②得x=
1200 |
7 |
當a=5時,解②得x=
1140 |
7 |
當a=6時,解②得x=
1100 |
7 |
當a=7時,解②得x=
7500 |
49 |
當a=8時,解②得x=150符合④.
故選A.
60 |
a |
2700 |
7 |
1500 |
7 |
1300 |
7 |
1200 |
7 |
1140 |
7 |
1100 |
7 |
7500 |
49 |