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The problem of profit The price of a certain type of TV set in the shop is 1200 yuan, which can make a profit of 20%. Now a unit has bought several sets of this type of TV set at the total price of 11500 yuan, so the shop still has 15% profit. How many TV sets has the unit bought?
Arithmetic solution:
Original price of TV set
1200 (1 + 20%) = 1000 yuan
The selling price of 11500 still has 15% profit, that is, including cost
11500 (1 + 15%) = 10000 yuan
Number of units bought
10000 △ 1000 = 10 sets
3 on the application of profit!
A store deals in clothes. It is known that the unit price of leather is 2.5 yuan when it is purchased. According to the market survey, the relationship between the sales volume and the sales unit price is as follows. In a period of time, when the unit price is 13.5 yuan, the sales volume is 500 pieces. If the unit price is reduced by 1 yuan, 200 pieces can be sold more. Please analyze, when the sales unit price is, can you make the most profit?
There are 100 peach trees in an orchard, and each peach tree bears 1000 peaches on average. Now we are preparing to grow a variety of peach trees to increase the yield. The experiment found that for each variety of peach trees, the yield of each peach tree will decrease by 2. If we want to increase the yield by 15.2%, how many kinds of peach trees should be planted? When planting how many kinds of peach trees, the fruit number is the most?
Please write out the formula
The first question: suppose that when the unit selling price is reduced by X Yuan, you can make the most profit, and the most profit is y
According to the meaning of the question y = (13.5-2.5-x) × (500 + 200X), it can be made according to quadratic function
Question 2: suppose the mass of each peach is a (assuming the mass of each peach is the same), more than x peach trees can increase the yield by 15.2%
a×[（100+x）×（1000-2x）-1000×100]/a×1000×100=15.2%
A variety of X peach trees can make the most fruit and set the most fruit as y
Y = (100 + x) × (1000-2x) can be made according to quadratic function
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