Questions (3 points for each small question, ***24 points)

1.

To understand the proportion of a batch of data in various ranges, this batch of data will

data clustering

The amount of data falling into each group is called (

)

A.

Sample size

B. frequency

C. frequency

D. Extreme poverty

2. The maximum value of a sample with a capacity of 70 is 14 1, and the minimum value is 60. take

class interval

For 10, it can be divided into (

)

A. 10 group

B.9 group

C8 group

D.7 group

3.

After the height of n students is grouped, in

frequency table

In "165.5 ~ 170.5cm", the frequency is 4 and 0. 10, while the frequency of "155.5 ~ 160.5cm" is m and 0.20.

)

A.40 and 8

B.8 and 40

C.40 and 4

D.4 and 40

4. The relationship between frequency m, frequency p and total data n is (

)

Morning+afternoon =n

B.n=mp

C.p=mn

D.

m=np

5.

(20 10

In order to know the physical condition of the ninth grade students, a school randomly selected 30 students, tested the number of sit-ups of 1 min, and drew the chart.

Frequency distribution histogram

According to the figure, the frequency of sit-ups between15 and 20 times is (

)

A.0. 1

B.0. 17

C.0.33

D.0.4