A practical problem, the solution of the first year of junior high school.

1) Average: (1800*1+510*1+250*3+210*5+150*3+120*2) 15=320 pieces.

Median: 210 pieces.

Mode: 210 pieces.

2) From the point of view of the average: a quota of 320 pieces is reasonable.

It is unreasonable to consider from the perspective of mode and median, because 210 is less than 320 Looking at the monthly sales volume of 15 people, only 2 people have more than 320 pieces, so it will be rated at 320 pieces, which will discourage the enthusiasm of most people, so it is more reasonable to position the quota at 210 pieces.

1800+510+250x3+210x5+150x3+120x2)÷15=320

The mean is 320, the median is 210, and the mode is 210

The quota for each person is 320, which is unreasonable to be 210, which represents the monthly sales volume of most people.

1) The average is 320, the median is 210, and the mode is 210.

2) Unreasonable. Because out of 15, only 2 people can reach it, and the remaining 13 can't reach it.

It is reasonable to set the sales at 210 pieces. Because more than half of the people can reach this goal.

1) Average: 320

Median: 210

Mode: 210

2) Unreasonable because only 18 out of 20 people can complete the task.

It should be set at 210 because 15 people can complete the task.

Average 4800 15 = 320

Median = (250 + 210) 2 = 230

Mode: 210

It is obviously unreasonable to use 320 as the sales volume quota, although it is an average but the above set of data is too discrete.

After removing the 1 highest number and 1 lowest number, the average value is (510+250*3+210*5+150*3+120) 13= 222

It is recommended to use the average number of 222 after removing 1 highest number and 1 minimum number as the fixed amount of sales.

Set up color TVs x 10,000 units, refrigerators 3 2x 10,000 units, mobile phones (10,000 units * means multiply.

1500x+

Figure it out yourself.

5 billion * 13 = ** subsidy.

Hope it helps!

Establish; At least x number of students participated in the group photo.

0 4x + less than or equal to 0 5x

Less than or equal to. Less than or equal to.

x is greater than or equal to 6

Answer; At least 6 students participated in the group photo.

Solution: Let the original ticket ** be X yuan, the percentage of ticket reduction is y, and the original number of tourists is z, then:

x(1-y) *3z/2 - xz ] / xz = y3(1-y)/2 -1 =y

3-3y-2=2y

Solve the equation to obtain: y=1 5=20%.

So that percentage is 20%.

Set: Admission Ticket Visitor Income.

First 1 1 1

Posterior 1-x 1+x (**).

Tickets x number of visitors = revenue).

So (1-x).

Solution x=20

A: This percentage is 20.