A.xy C.x≤y D.x≥y
According to the question, the average cucumber he bought was 30x+20y50 per catty.
After selling at the price of x+y2 yuan per catty, I found myself losing money.
Then 30x+20y50 > x+y2.
Solution, x > y.
So the reason for losing money is x > y.
So choose B.
In response to the policy of benefiting farmers by "home appliances going to the countryside", a shopping mall decided to buy 80 refrigerators of three different models from manufacturers, of which the number of type A refrigerators was twice that of type B refrigerators, and the total purchase amount of three refrigerators did not exceed132,000 yuan. It is known that the ex-factory price of type A, B and C refrigerators is1.each refrigerator in 200 yuan.
(1) How many refrigerators have you bought at least?
(2) If the number of Class A refrigerators is required not to exceed the number of Class C refrigerators, what are the procurement plans?
Solution: (1) If you buy X B refrigerators, you will buy 2 A refrigerators and 80-3 C refrigerators.
According to the meaning of the question,1200× 2x+1600x+(80-3x )× 2000 ≤132000.
X≥ 14 for solving this inequality.
∴ Buy at least 14 type B refrigerators;
(2) According to the meaning of the question, 2x≤80-3x.
X≤ 16 for solving this inequality.
It is known from (1) that x≥ 14.
∴ 14≤x≤ 16
And ∵x is a positive integer
∴x= 14, 15, 16.
So, there are three purchase schemes.
Scheme 1: There are 28 Class A refrigerators, 28 Class B refrigerators 14 refrigerators and 38 Class C refrigerators.
Scheme 2: 30 Class A refrigerators, 35 Class B refrigerators 15 refrigerators and 35 Class C refrigerators.
Scheme 3: 32 Class A refrigerators, 32 Class B refrigerators 16 refrigerators and 32 Class C refrigerators.